Conclusion

Getting started with testing to such an extreme degree is difficult. The key is to just get started. A comprehensive suite of tests is collected over time, not created in the last few weeks of a project. Start collecting them today instead of tomorrow. You don't need to know what you are doing you can learn as you go. Skipping the tests always takes longer, even if it needs to be done by tomorrow. When you create the tests first, it seems as if you are not making much progress during the first 30 minutes. You will make up for it during the hours that follow when things are still progressing steadily and under control.

It can be a particularly daunting task to have to start writing tests when a large body of code already exists without tests. Don't become overwhelmed. Add tests when you need to fix a bug. Add tests when you need to change something. Add some black-box-like unit tests to quickly cover stable portions of the system. What you will soon find is that areas of code being changed often quickly acquire more than adequate test coverage.

Software that was delivered on time but has so many bugs that it is rendered useless should not be considered delivered on time at all. So often, we see projects in which time is scheduled at the end of the project for final testing. This time is always overrun by development because testing was not performed as part of the development process. The only way to ensure that software remains usable in the future is to test it today.