What is your reason when you use outer perspective to answer a question?

Outer perspective the in the context of answering a question out of what the OP really ask for.

Example: When someone ask “How could I make my friend’s boyfriend to love me?”
Most of the answers would be: “He’s not your boyfriend,find someone else!” or “Why would you want to betray your friend and steal her bf?”

Of course there would be no accurate answer according to what the OP ask for. Plus,many people will take it personally and judge this user based on this question.

I’m not against this way as that’s the freedom of each poster to do so but I’m curious why some people prefer to stand out of the line(outer perspective) rather than give what the OP ask for? Why won’t avoid to answer the question if you have nothing valuable for the OP?