I believe you are getting it. The key is that you need to understand what you want well enough to explain it to this stupid computer. As you get more practice, you will learn which requirements you really need to specify well and which you can slide on.

Unfortunately, bright and abstract thinking are sort of independent of the way to think about this kind of problem. You almost have to look at it as if the computer is going to exploit anything you haven't specified well. The worst part is that sometimes an underspecified program will appear to work and lull you into a false sense of security.

The answers you are getting are from people that have been bitten over and over again by times when they thought they knew what they were doing.

Welcome to the wonderful world of programming!