Not everyone can say, 'I'm going to write a classic today.' If that was the case, we'd all be doing it.
I think it's like music for the sake of music, and a lot of the words stem from liking music a lot, wanting to be a good band and having a good sense of humour, and living in a situation where we're free to pretty much do what we want.
A signal is comprehended if it serves to make us notice the object or situation it bespeaks. A symbol is understood when we conceive the idea it presents.