User Acceptance testing

User Acceptance Testing is also called Beta testing, application testing, and end-user testing. Whatever you choose to call it, it’s where testing moves from the hands of the IT department into those of the business users. Software vendors often make extensive use of Beta testing, some more formally than others, because they can get users to do it for free.

By the time UAT is ready to start, the IT staff has resolved in one way or another all the defects they identified. Regardless of their best efforts, though, they probably don’t find all the flaws in the application. A general rule of thumb is that no matter how bulletproof an application seems when it goes into UAT, a user somewhere can still find a sequence of commands that will produce an error.

To be of real use, UAT cannot be random users playing with the application. A mix of business users with varying degrees of experience and subject matter expertise need to actively participate in a controlled environment. Representatives from the group work with Testing Coordinators to design and conduct tests that reflect activities and conditions seen in normal business usage. Business users also participate in evaluating the results. This insures that the application is tested in real-world situations and that the tests cover the full range of business usage. The goal of UAT is to simulate realistic business activity and processes in the test environment.

A phase of UAT called “Unstructured Testing” will be conducted whether or not it’s in the Test Plan. Also known as guerilla testing, this is when business users bash away at the keyboard to find the weakest parts of the application. In effect, they try to break it. Although it’s a free-form test, it’s important that users who participate understand that they have to be able to reproduce the steps that led to any errors they find. Otherwise it’s of no use.

A common occurrence in UAT is that once the business users start working with the application they find that it doesn’t do exactly what they want it to do or that it does something that, although correct, is not quite optimal. Investigation finds that the root cause is in the Business Requirements, so the users will ask for a change. During UAT is when change control must be most seriously enforced, but change control is beyond the scope of this paper. Suffice to say that scope creep is especially dangerous in this late phase and must be avoided.

Sample Entry and Exit Criteria for User Acceptance Testing

Entry Criteria

• Integration testing signoff was obtained
• Business requirements have been met or renegotiated with the Business Sponsor or representative
• UAT test scripts are ready for execution
• The testing environment is established
• Security requirements have been documented and necessary user access obtained

Exit Criteria

• UAT has been completed and approved by the user community in a transition meeting
• Change control is managing requested modifications and enhancements
• Business sponsor agrees that known defects do not impact a production release—no remaining defects are rated 3, 2, or 1