The test pyramid is a great model for designing your test portfolio. However, the bottom tends to fall out when you shift from progression testing to regression testing. The tests start failing, eroding the number of working unit tests at the base of your pyramid. If you don't have the development resources required for continuous unit test maintenance, there are still things you can do.

Continuous operation tests find important bugs, partly as a result of their long operation and partly by increasing the probability of finding statistical bugs. However, CO tests have their own downsides. Mandating a periodic reset or reboot can work around these issues, as well as save time and cost for testing, reproduction, debugging, and fix verification.

There are a lot of misunderstandings about exploratory testing. In some organizations exploratory testing is done unprofessionally and in an unstructured way—there's no preparation, no test strategy, and no test design or coverage techniques. This leads to blinds spots in the testing, as well as regression issues. Here's how one company made its exploratory testing more structured.

We like to hope that we will consider all possible situations when devising our tests, but it’s all too easy to overlook the unusual cases. That’s the benefit of random test generators. We might feel comfortable after testing a few dozen test cases; these tools generate hundreds. With more stuff getting tossed at the wall, there is a greater likelihood that something interesting sticks.