I think the thing that makes someone still poor is that he doesn't have a clear vision about money, he thinks that money is a normal thing and is not his target or hope, when he gets a lot of money it will be easy to spend it according to his pleasure, he always thinks that tomorrow there will be the same money.
What you say is also partly true, but that is not the only reason. No one wants to be poor, but everyone's situation is different. Many people are unlucky to live in a poor country with a corrupt government, no matter how hard he tries, he will never get out of poverty. Or those who always work hard, but there are too many events in life, so no matter how much you work, you can't accumulate enough to become rich. There are many reasons and causes that make someone poor forever.