It's a simple question for some people but complex for others.
For the overwhelming majority the answer is obvious, you need to know if you can pay the bills or simply earn more than your own job.
In a way, you are correct, that is the basis, correcting your strategy, adapting as much and as quickly as possible to the new strategies or movements of regular players who have studied your game.
But what you need to know and often doesn't even cross your mind... Poker is not just a game of skill and luck, you must include your mental state, so to progress or even be a profitable player, you need to take care of your mind . Not just during the game, but that includes everything away from the table, namely your problems. If you don't look for forms of self-control and mental stabilization, you can be absolutely sure that you won't make progress in the long run and your profit chart will look like a roller coaster.
For many people, meditation is a good path, but the ideal is to first have self-knowledge and really know what works for you.
That done, already knowing what your game is and how to keep your mind healthy, you are on the right path to make a living from poker, just keep improving your game until you reach your goal.
And you, what do you think about it?