Marketing. Marketing is the weakest skill most artists have. Most artists who have "made it big" have done so because of actions taken by a team. Marketing is the difference between success and failure. Most singers, musicians, actors, artists, and entertainers fail miserably at marketing themselves.
Marketing brings about awareness of your existence as an artist. If the world does not know about you and why you are unique and what your art looks like, you may as well be living in a little shack out in the middle of the forest, with no roads which lead to it. You are a hermit. You are unknown. You are hidden. You need to be discovered. If you leave it up to chance, don't count on anything changing.
What can you do, to be found, to be known?
You will be successful to the extent that you know how to market. I wish that this weren't true, because it takes work and time and attention. It also takes some education. You don't have to get a bachelors or masters degree but you do have to know what works and what doesn't work. This is the real make or break point in a career. If you hire someone to do it for you, you might be doing some outrageous things that you are unwilling to do. Think Lady Gaga, Miley Cyrus, and Madonna, years ago. What if you don't like wearing a meat suit, strange shoes, being overtly sexy (if not vulgar) or being outrageous in other ways? The truth is that everyone did not do those things but the truth is also that you absolutely have to know how to attract attention.
Ask me how.