The trick generally is to break programs into pieces and have those pieces be individually testable and so then when you move on to the other pieces you treat it as a black box knowing that it either works or... ...
As you get to the end of the project you want to run all the tests cases against one version and make sure that you know that that version passed everything. And so as you get late in the project... ...
When you develop software, the people who write the software, the developers are the key group but the testers also play an absolutely critical role. They're the ones who ah, write thousands and thousands of examples and make sure that... ...
Even when I wrote Basic myself the day before I burned it into a computer I wasn't making design changes. I didn't have a testing team. I did all the testing myself. And there was no project methodology or schedule... ...
