First of all this was in the mid 1990s and the idea of unit testing hadn’t happened yet. Even now I never do it, it’s too much work and the whole idea that a code change breaks something else is exactly what OOP is intended to prevent.
My whole point is that good OOP creates small and simple functions that can be fully analyzed, not all intertwined.
I do my testing when a component is finished, not before I write it. And in the case I mentioned I did less than an hour and only found minor bugs, nothing that would have held up release.
Most developers make no effort to write legible code so it’s no wonder they have to do extraneous work like unit tests. I almost never use a debugger, I can eyeball the code and execute it in my head.
I’ve been at this 32 years and it’s just stunning that after all this time legibility has gotten even worse. People compulsively adopt formatting gimmicks and get satisfaction out of others having trouble reading it.