I like to give the benefit of the doubt to people. When a question is asked, most of the time, even if the question is not relevant to me or anyone I know, it could be a legitimate doubt that the poster has. However, sometimes, I'm sure that there is abuse of the system with people posting questions they don't care about just for upvotes and participation points.
Overall, I think we should not judge questions too harshly as there will always be someone who might be interested in the answers.
Well what makes a question relevant is the idea other people will get from the answers that those who replied to the question get, moreover most of the questions asked are very good questions...
A fraction of all the questions on musing.io are so horribly worded that nobody can begin to know how to answer them. Those questions might be spam if somebody replies asking for more details and the person who originally posted the question never responds back.
Most of the questions here seem spammy. But you really can't tell if a person is really ignorant or just wants the vote.
I've met quite a good number of people who asked absurd questions and I felt they were irrelevant and dumb. But all they wanted was to be enlightened.
And that's the general reason we ask questions, to be enlightened.