Obviously you need to have ability and perseverance if you want to be a professional musician. Right now I am trying to make the calculation as to how much sense it makes to do what I really want and study at a Singapore music school to learn some of the things that I do not really know just yet. I am not good enough to make a living at it right now, that much I am pretty sure of. However the question that I have is whether or not I would ever be able to really make a living at it. I am sure that I could be happy if I did reasonably well. For example the likeliest outcome is that you end up teaching at a school. You would probably need to be able to teach a high school band, although that has nothing much to do with my personal interests. I play keyboards and guitar. In fact the best chance for me to make money is probably playing bass if I get to do what I want.
In fact the bass player is really important, along with the drummer. They basically build a framework upon which the other vocalists and musicians can work. You can not do much else without the foundation to build upon. In fact it is not really that interesting if you look at being a musician as a fantasy. The girls are not really going to go wild when the bass player lays down a backbeat for the singer to sing to. However you can make a lot of money if you are really good enough, because those other guys will not be able to make much music if there is not a rhythm to play along to. Writing music for TV and movies is also a great way to earn money.