These are excellent observations; I'd add that it is often impossible to write an explanation that will be clear to all readers; some of the best writers circumvent this by stating the same thing in multiple ways, but this can be challenging to achieve without becoming tedious. Hence the value inherent in collecting multiple (conceptually-identical) answers and multiple (cross-linked duplicate) questions... Also, the ability to use an editor's work to view your work through someone else's eyes is one of the most-overlooked educational aspects of Stack Overflow. —
Shog9 ♦ Sep 9 '15 at 16:47