It’s about the same as building a startup I’d say. Luck plays a huge role (and there are lots of people trying to divine rules extrapolated from their lucky experience to help you) but I’d also say the music (product) really does need to be incredibly good for you to make it. But maybe it isn’t needed initially as long as you get feedback and develop product market fit for your music, but that would be considered very uncool in the music industry.