Just my opinion:
If you are getting into the indie game dev scene for financial reasons, then keep this in mind:
1. There are far more practical means of securing a stable income in other career fields.
2. Financial gains tend to come at the completion of a project, which for games of high quality will probably take multiple years.
Thus, those using financial gain as an incentive for the development of a project will probably not be able to handle the significant, delayed wait combined with the significant workload required to complete high-quality projects.
3. Most projects don't make it to completion due to various reasons, keep this in mind in terms of how soon you'd get a return on investment.
4. (My opinion) It's hard to make a good game, even more so as an indie. It often requires a certain willpower that goes beyond motivation, beyond financial incentive, a willpower that carries you through the darker times when it feels like you are getting nothing done.
So, for your own sake, I recommend focusing on the expression of your own ideas, your own stories rather than how much money you want to make.