A reader question:
What if I know what appeals to me but I am awful at it or everyone else thinks I'm awful at it? For example, some people love to sing but that doesn't mean they are good singers.
If you're basing your career options solely on the things you're interested in, you are leaving incredibly rewarding possibilities on the table.
I know this sounds hard to believe. But your approach of looking to subject matter for the answer, just like we're taught to do in school, is very limited. My real answer is to entirely change the way you understand your career options, because I think that will solve your real problem: trying to figure out what your career should be.
But, if you're set on this interest of yours, here are your options:
Option 1: Get better at it.
To use your example, if you really want to be a singer, get better at it! Train and practice and try to make it your career. Keep a day job going while you work on your chops, and eventually try to make it so your singing career eclipses your day job and it makes more sense to quit the day job than to keep it.
The world will tell you if it values you as a singer as you try to get work.
The unfortunate thing is, just because you become excellent at something doesn't mean you can make a living at it. (Sorry, Van Gogh.)
There are no guarantees. But people who are really driven to make their interest their living go for it anyway. I'm thinking of the thousands of actors in Los Angeles and New York, with varying levels of talent, who KNOW that this is what they want to do. They train, they wait tables, the make sacrifices, and when they get paid to be an actor, it makes is all worth it.
If you don't have that kind of drive for singing (or whatever you might be awful at), then it's probably not your Homecoming Career.
Option 2: Don't get better at it, and try it anyway.
Sometimes people who are not good at things end up making a lot of money at them, anyways.
I'm sure you can think of a singer, writer, or actor you've seen and thought, "Who gave this guy a recording deal/publishing deal/television show?"
Talent matters, but sometimes opinion matters more. If people like you in spite of your deficiencies, you could still do really well. But it doesn't work if you're self-conscious. You have to own it and rock doing it how you do it. That makes this option kind of a long shot, because it takes either a certain kind of confidence or lack of self-awareness to pull it off.
But if you start before you're really good, you might find yourself back to Option 1 because the practice you get will make you better.
Option 3: Keep it as a hobby and make money doing something else.
The interest you love doesn't have to be the way you make money. And I don't mean sing on the weekends while you have a boring desk job the rest of the week. You can have a career you love without doing the "follow your passion" thing.
It can be wonderful to take the pressure off the thing you enjoy being your source of income. A lot of people worry that if they don't try to make their passion their career that they're giving up and missing out on their one chance at loving their work. I'm here to tell you: not so.
If you're awful at what appeals to you, you do have options. But if you're missing that spark, the gumption, that DRIVE to do it, then that's what you should be looking for.