Archive for August, 2010
Tuesday, August 24th, 2010 by Rex Black
Many of our clients and course attendees ask about templates. We have many templates posted on our Basic Library and our Advanced Library. A few worth particular mention are:
The last one isn’t actually a template, but it’s something many people find interesting.
If there’s some other template you need, search the Basic Library and Advanced Library. If you still don’t find it, post a comment here on the blog letting the readers and me know what you’re looking for. Maybe someone can help.
Remember, though, a template is not an excuse to turn your brain off. Be sure to use templates thoughtfully.
Tags: software test documentation, software testing, software testing templates Posted in best practices, risk based testing, software test templates, software testing | 2 Comments »
Friday, August 20th, 2010 by Rex Black
I took a few moments today to record another video blog entry, which you can find at Regional Software Testing Immaturity: Fact or Fallacy?
Here’s the synopsis: I’m in Los Angeles, on my way to the STANZ conference in Australia and New Zealand. That and other recent international trips have gotten me thinking about something that I often hear at such international conferences, which are comments along the lines of, “You know, software testing as a profession and a practice is really immature in region X,” where region X might or might not be where I’m at. Based on my experience with clients around the world, though, the gap isn’t as big as people often think it is. Is software testing actually significantly less mature in some regions than others? What has your experience been? I’d be interested in opinions, case studies, and stories from you, especially the many international readers of this blog but also people in North America.
Tags: software test management, software testing, testing immaturity Posted in best practices, software test management, software test metrics, software test outsourcing, software testing | 5 Comments »
Tuesday, August 17th, 2010 by Rex Black
A couple recent events might seem to indicate a greater appetite–and need–for greater technical skills. I thought I’d leave a quick video blog post on this topic–see Technical Testers Blog. Let me know what you think. Are we in need of stronger technical skills? Do you have technical skills? Do you need and want technical skills?
Tags: software test training, software testing, technical testers Posted in software testing | 7 Comments »
Thursday, August 12th, 2010 by Rex Black
When I wrote my book Critical Testing Processes in the early 2000s, I started with the premise that some test processes are critical, some are not. I designed this lightweight framework for test process assessment and improvement in order to focus the test team and test manager on a few test areas that they simply must do properly. This contrasts with other, more expansive, and more complex frameworks. In addition, the Critical Testing Processes (CTP) framework eschews the prescriptive elements of other frameworks because it does not impose an arbitrary, staged maturity model.
What’s the problem with prescriptive models? In our consulting work, we have found that businesses want to make improvements based on the business value of the improvement and the organizational pain that improvement will alleviate. A simplistic maturity rating might lead a business to make improvements in parts of the overall software process or test process that are actually less problematic or less important than other parts of the process simply because the model listed them in order.
CTP is a non-prescriptive process model. It describes the important software processes and what should happen in them, but it doesn’t put them in any order of improvement. This makes CTP a very flexible model. It allows you to identify and deal with specific challenges to your test processes. It identifies various attributes of good processes, both quantitative and qualitative. It allows you to use business value and organizational pain to select the order and importance of improvements. It is also adaptable to all software development lifecycle models.
Since CTP focuses on a small number of processes, how are those processes selected? What is a critical testing process? Here’s a quick way to think about it: If a test team executes the critical testing processes well, it will almost always succeed, but if it executes these activities poorly, even talented individual testers and test managers will usually fail. Let’s expand this definition a bit.
First, I defined a process as some sequence of actions, observations, and decisions. Next, I defined testing as the activities involved in planning, preparing, performing, and perfecting the assessing of the quality of a system. So, with a definition of a test process firmly in hand, what makes a test process a critical test process? I applied four criteria:
- Is the process repeated frequently, so that it affects efficiency of the test team and the project team?
- Is the process highly cooperative, involving a large number of people, particularly cross-functionally, so that it affects test team and project team cohesion and cooperation?
- Is the process visible to peers and superiors, so that it affects the credibility of the test team?
- Is the process linked to project success, in such a way as to affect project team or test team effectiveness?
In other words, a critical test process directly and significantly affects the test team’s ability to find bugs, build confidence, reduce risks, and generate information.
Based on these criteria, I identified the following twelve critical testing processes:
- Testing. The overall process, viewed at a macro, strategic level. It consists of eleven constituent critical testing processes.
- Establishing context. This process aligns testing within the project and the organization. It clarifies expectations on all sides. It establishes the groundwork for tailoring all other testing processes.
- Quality risk analysis. This process identifies the key risks to system quality. It aligns testing with the key risks to system quality. It builds quality and test stakeholder consensus around what is to be tested (and how much) and what is not to be tested (and why).
- Test estimation: This process balances the costs and time required for testing against project needs and risks. It accurately and actionably forecasts the tasks and duration of testing. It demonstrates the return on the testing investment to justify the amount of test work requested.
- Test planning. This process builds consensus and commitment among test team and broader project team participants. It creates a detailed map for all test participants. It captures information for retrospectives and future projects.
- Test team development. Since testing is only as good as the team that does it, this process matches test team skills to the critical test tasks. It assures competence in the critical skills areas. It continuously aligns team capabilities with organizational value of testing.
- Test system development. This process ensures coverage of the critical risks to system quality. It creates tests that reproduce the customers’ and users’ experiences of quality. It balances resource and time requirements against criticality of risk. It includes test cases, test data, test procedures, test environments, and other support material.
- Test release management. If we don’t have the test object, we can’t test it. If the test items don’t work in the test environment, we can’t test them. If each test release is not better than the one before, we’re not on a path for success. So, this process focuses on how to get solid, reliable test releases into the test environment.
- Test execution. This process, the running of test cases and comparison of test results against expected results, generates information about bugs, what works, and what doesn’t. In other words, this is where the value of testing is created. This process consumes significant resources. It occurs at the end of the project and gates project completion.
- Bug reporting. This process creates an opportunity to improve the system (and thus to save money). While test execution generates the value of testing, this process delivers part of the value of testing to the project team, specifically the individual contributors and line managers. It builds tester credibility with programmers.
- Results reporting. This process provides management with the information needed to guide the project. It delivers another part of the value of testing to the project team, particularly line managers, senior managers, and executives. Since test results are often bad news, it separates the message from messenger. It builds tester credibility with managers
- Change management. This process allows the test team and the project team to respond to what they’ve learned so far. It selects the right changes in the right order. It focuses efforts on the highest return-on-investment activities.
You might notice that I’ve described each of these processes in terms of what an optimal process will achieve. If the process does not achieve those standards of capability—and more—then it is not optimal and has room for improvement.
How can you use CTP for assessment and improvement? Test process improvements using CTP begin with an assessment of the existing test process. This assessment will identify which of the twelve test processes are currently done properly and which need improvement. The assessment results in a set of prioritized recommendations for improvements. Whether you use the framework to do your own assessment or hire a consulting firm like RBCS to do it, the assessment should base the recommendations on organizational needs.
Since the assessments are tailorable, they can vary depending on the specific organization and its needs. We have done narrowly focused CTP assessments that looked only at one test team, we have done CTP assessments that looked only at a one or two test processes like the test system, and we have done broad CTP assessments that looked at everything that affects quality. So, while CTP assessments vary, we tend to examine the following metrics during a CTP assessment:
- Defect detection percentage
- Return on the testing investment
- Requirements coverage and risk coverage
- Test release overhead
- Defect report rejection rate
In addition, we also tend to evaluate the following qualitative factors, among others, during a CTP assessment:
- Test team role and effectiveness
- Usefulness of the test plan
- Test team skills in testing, domain knowledge, and technology
- Value of the defect reports
- Usefulness of test result reports
- Change management utility and balance
Once an assessment has identified opportunities for improvement, the assessor will develop plans to implement this improvement. While the model includes generic guidelines for process improvement for each of the critical testing processes, the assessor is expected to tailor those heavily.
I designed the CTP model to be very flexible. It does assume the primary use of an analytical risk-based testing strategy, balanced with a dynamic testing strategy. However, you can adapt CTP to use other test strategies primarily, such as requirements based, checklist based, or model based.
There are some five to ten metrics for each critical testing process, along with some qualitative evaluations. Now, we don’t typically look at every metric for every process on every single assessment because the selected metrics, like the model itself, are tunable. This results in a customer-centric assessment.
So, what is the value of a CTP assessment? CTP, like any other process model, provides a starting point, a standard framework, and a way of measuring your processes. A process assessment using a process model identifies opportunities to improve your current process that could not be identified by applying continuous process improvement techniques, such as Deming’s Plan-Do-Check-Act (PDCA), to your current existing processes. This is true because techniques such as PDCA are incremental improvement techniques, while process models allow provide a method for quantum leaps in process improvement through the introduction of known best practices.
Properly done, CTP assessments deliver specific recommendations, along with the order in which to implement them. When my associates and I carry out CTP assessments for clients, we typically deliver a 50 to 100 page report with our assessment of the critical testing processes, our recommendations for improving them, the business justification for the improvements, and a roadmap for implementing those improvements. If you look at any two of our assessment reports, you might see very similar recommendations but in very different order. Why? Because each client has a different level of opportunity associated with the recommendation. In some cases, constraints or preconditions can influence the order. Those constraints and levels of opportunity tend to be unique from one organization to another, and a non-prescriptive model adapts to those unique organizational needs.
Let me close with an important note: Whether you use CTP or some other test process assessment model, don’t use process assessments as a one-time activity. Having done an assessment and found opportunities to improve, you should—of course—improve. Furthermore, at regular intervals, you should reassess to see the effect of the changes. Based on that reassessment, you should course correct your process improvement.
Posted in best practices, software test management, software test metrics, software testing | No Comments »
Friday, August 6th, 2010 by Rex Black
The process of negotiating a software testing budget can be painful. Some project managers view testing as a necessary evil that occurs at the end of the project. In these people’s minds, testing costs too much, takes too long, doesn’t help them build the product, and can create hostility between the test team and the rest of the development organization. No wonder people who view testing this way spend as little as possible on it.
Other project managers, though, are inclined to spend more on testing. Why? Smart software managers understand that testing is an investment in quality. Out of the overall project budget, the project managers set aside some money for assessing the product and resolving the bugs that the testers find. Smart test managers have learned how to manage that investment wisely. In such circumstances, the test investment produces a positive return, fits within the overall project schedule, has quantifiable findings, and is seen as a definite contributor to the project.
As Phil Crosby wrote, “quality is free.” This can be demonstrated by breaking down quality related costs as follows:
Cquality=Cconformance+Cnonconformance
Conformance costs include prevention costs and appraisal costs. Prevention costs are moneys spent on quality assurance—tasks like code reviews, walkthroughs, or inspections, requirements definition, and other activities that promote good software. Appraisal costs include moneys spent planning test activities, developing test cases and data, and executing those cases—once.
Nonconformance costs come in two flavors, internal failures and external failures. The costs of internal failure include all expenses that arise when test cases fail the first time they’re run—as they often do. Think through the process: The tester researches and reports the failure, the developer finds and fixes the fault, the build engineer produces a new release, and the tester retests the new release to confirm the fix and to check for regression. The costs of external failure are those incurred when, rather than a tester finding a bug, the customer does. In these cases, not only does the same process described above occur, but you also incur the technical support overhead and the more expensive process of releasing a fix to the field rather than to the test lab. In addition, consider the intangible costs: Angry customers, damage to the company image, lost business, and maybe even lawsuits.
Two observations lay the foundation for the enlightened view of testing as an investment. First, like any cost equation in business, we will want to minimize the cost of quality. Second, while it is often cheaper to prevent problems than to repair them, if we must repair problems, internal failures cost less than external failures.
Let’s look at a hypothetical case study, illustrated in the figure below. Assume we have a software product in the field, with one new release every quarter. On average, each release contains 1,000 “must-fix” bugs—unacceptable defects—which we identify and repair over the life of the release. Currently, developers find and fix 250 of those bugs during development, while the customers find the rest. Cost of quality accounting shows that, on average, each pre-release defect costs $10, while field failures cost $1,000. As shown in the “No Formal Testing” column in the figure below, our cost of quality is three-quarters of a million dollars—and customers are mad! So, we invest $70,000 per quarterly release in a manual testing process. The “Manual Testing” column shows how profitable this investment is. The testers find 350 bugs before the release, which cuts almost in half the number of bugs found by customers. Not only does this make the customers happier, but, because cost of quality accounting shows that we pay only $100 on average for each bug found by testers, our total cost of quality has dropped to about half a million dollars. Our ROI on this $70,000 investment is 350%.
 Return on the Software Testing Investment
In some cases, we can do even better. For example, suppose that we invest $150,000 in test automation tools, amortizing that investment over twelve quarterly releases, and manage to find about 40% more bugs? Finding 500 bugs in the test process would lower the overall customer bug find count for each release to 250—a huge improvement over the initial situation. In addition, cost of quality would fall to a little under $400,000, a 445% return on investment.
Cost of quality analyses on software process improvement bear out these figures. We have seen clients who enjoy return on the software testing investment that ranges anywhere from 50% to as high as 3200%. While software testing is only part of achieving software quality, it is an important part, and a substantial investment is justifiable to achieve such phenomenal gains.
To get started, you’ll need a management team wise enough to look at the cost of quality over the entire life of the software release. A management team that ignores the long term and focuses just on the budget required to get the software out the door initially does not see testing as an investment. Quality is given lip-service when the only priorities are shipping something—anything—on a given schedule and within a given budget.
However, having supportive, far-sighted management is only a necessary—not a sufficient—condition for achieving positive returns on your test investment. Just as in the stock market, there are right and wrong ways to invest. Picking the right tests, managing the appropriate quality risks, using the proper tools and techniques, and driving testing throughout the organization will result in optimal returns, while failure in any one of these areas can mean disappointing or even negative returns. These topics come up again and again in this blog, but if you’d like me to address one or more of them specifically, please let me know.
Posted in software quality, software test management, software test metrics, software testing | No Comments »
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