I also don't dare to quit my real world job, to focus on trading. As I said before, I have a family that I have to provide for while my trading skills are not good because I am not a professional trader. so so far trading is just a side job for me, to get additional income.
I really appreciate those who have the courage to focus more on trading, and as you said they must have gone through a long process.
If you can do both at the same time, why quit?
I mean as long as you're happy with your work while doing trading, and it doesn't cost you too much time then by all means, don't quit.
If you're profitable in trading, but you feel that you can't make it as a stable income then don't quit. Now if you're making profits already that's more than your monthly salary in your work and you're doing it consistently then it's your decision now if you will quit on your job or not. Traders aren't unemployed, but I would call them as self-employed, or more of a work-from-home type of worker. At the end of the day, there are traders out there that are making too much money on trading already that they don't need to spend 8 hours to be paid minimum.
Learning trading, and be an expert with it will cost you money, and time, but once you become an expert, it will be worth it. It's a skill that can yield you money if you know what you're doing, same if when you have a skill and you're offering it with others.