The most common I have seen is to obsess over code as an ends in itself. Writing pretty code when the solution doesn't really require it. The other is prematu

The most common I have seen is to obsess over code as an ends in itself. Writing pretty code when the solution doesn't really require it. The other is premature optimization, where all code must be fast, regardless of whether the problem requires it. These both lead to lacking a "get it done" attitude that I've seen in the self-taughts.