I think you misunderstood her original post. She wasn't suggesting that OP become a music teacher because they won't make it as a performer, she was asking about their current circumstances (as in "You mentioned your theory teacher, does that mean you are in college?")
Just clarifying to avoid unnecessary arguing that happens so often here 
I understood DC completely, the point I was making is a certain mindset "those who can't, teach".
Many people enter higher education with the mind set of I get my degree, enter some competitions and find an agent.
Wrong!
I can remember clearly, some of my peers responding, when asked, what is your next step, literally: "I will put on a few recitals, enter some competitions and take it from there". They did so, and did not win, and did not find an agent, and most of them left the profession.
The ones who are still making music, were the quieter ones who did, music. They taught, they performed, they composed, they arranged, and were in many ways self sufficient. They understood that their scope for music making would not be international, or national, but local, instead focusing there efforts of realistically becoming a music professional, within their means.
The ones who thought they would fall into a career, were surly mistaken and quit, mainly because they were not willing to work for it. Secondarily, because the reality failed to meet unrealistic expectations.
As DC said, of course, you do need some level of proficiency to even accompany, or get the gigs; but the unrealistic expectation of being an international concert pianist is just that unrealistic. That pedigree of music was breed for the role; that is, from a family, for whom this was always the expectation, having access to good instruments, teaching with music as the sole priority in their life. Just watch videos of them in their infancy; many big names were already at an entry-level of professional proficiency before they left single digits. The time spent at university honing their maturity; they did not have a point to prove because they already had it, all to simply make music.
Do you think a young Yundi Li had to battle with anyone regarding his art; "Go get a real job", etc. Do you think Latista had to beg her parents for access to a decent piano? No they were encouraged, and respected at a young age, with a support system in place. It's also worth mentioning that there was already a musical connection there who was able to offer advise on the best route; different form their teacher.
As some one previously mentioned, one track.