Of course there are people who have chosen to be poor, but the majority of poor people haven't chosen that. They just were born poor and were unsuccessful in their tries to become rich. If you mean trading can help someone to become rich, it is possible, but I think it is more likely that to become rich through some other job. A job that requires more knowledge than trading.
No, no one chooses to be or stay poor; it's just that they don't know what they need to do so that they can have better financial situations, and they also lack proper opportunities to make that happen. Secondly, even if it's possible for one to get rich through trading, even though I don't think so because trading is to make profits and not to become rich, but for someone to even have the slightest possibility of that happening from trading, they will need to have a good enough capital to begin with, and how would a poor person have a capital good enough to make it possible for them to make good profits from trading?
And finally, a job also cannot make someone rich, unless they have got a job in a very big company that pays them too much money for the position, but such things are not for everyone, and only a small number of people in the whole world get to have such jobs, and the majority only gets jobs that will allow the to go from month to month with their expenses, and you can't even have enough money to save some of it when you are doing a job.
A business can make one rich over time, but it also requires an initial investment, and then proper management skills for it to succeed.