Because much of the time you just haven't realized yet that you don't really know shit about shit, and good friends communicate in a variety of different ways about different subjects, sometimes just listening, sometimes actually helping someone with an issue they've asked for help with. Lack of versatility in that area means one will probably struggle to form more than the most superficial of relationships, because ironically it ends up being more shallow to think you're in a position to do something more impactful than offering your time to listen.

It's like coming onto a new team as a junior software dev thinking you'll introduce whatever hot new build tool or refactor the code that sucks that someone wrote 15 years ago, and then getting fired because you're clueless.