Trading is not easy and even if you have the time and knowledge there is no guarantee that you will definitely make a profit from it. Making profits from trading is extremely difficult, which is why most people prefer to invest for the long term.
It just depends on where you live and how good you are with your trading skill to even bother to think to make trading as your full-time income source. Full-time trading isn't good as you think and not everyone could achieve this due to the stress and good strategy to maintain the income, also like I said earlier not everyone have enough time to bother to check the graph often because of their jobs and activities.
If you live where it's difficult to get the job and you are already work there, I don't think sacrifice your job to do something inconsistent in terms of income is even worth it to think.