Inevitably groups form around a skill, programmers hang around programmers and so on. Since programmers "create" all the value we believe we should get paid the most etc.
Alas schools emphasise "hard" skills (programming, math, doctors, lawyers etc) and those are all good jobs that make decent money. They ignore "soft" skills like selling, marketing, and so on.
In truth sales and marketing are orders of magnitude more valuable, and their pay reflects that. There are a lot of pharma reps, realtors, insurance salesman that earn mega bucks.
This is not something the average hacker wants to hear. I expect to get down-voted for saying it. But if you're reading this, and you're thinking of starting out on your own, then I recommend you consider;
Who will you sell to? How will you reach them? What can they afford?
Only then start thinking about what to make.