[tboyd47]

This is the point I was trying to make in my top-level comment, although you expressed it much more eloquently.

Practical programming involves dealing often with problems that are messy, obscure, and vague. They don't teach you that in CS101. Some beginners detest that class of problems because purism is trendy, but they still have the patience to work through them, and because those moments are what teaches you programming, they make progress despite their own objections.

Some people simply don't have the patience. They put up a lot of resistance to spending time on any problem that's not immediately recognizable to them. As a result, they never advance in the discipline.