I agree with this assumption or ideology, because basically everything must start from ourselves, including making ourselves rich. Because how can someone want to become rich, if for example that person does not have the capacity or thinking that is capable of bringing that wealth. The point is that if you talk about mental matters too, of course you can see the difference. Because people who have the potential to become rich have a very strong mentality and it is different from the mentality of people who do not have the potential to become rich. For example, people who have the mentality of being rich, even though they are poor, will definitely try hard to change their lives to be better. Usually people who have the mentality of rich people never seem to get tired, and always seek new knowledge every time they meet new people. Then this knowledge was tried and applied by himself personally. In contrast to people who have a poor mentality, they do not seem to have a strong desire to change their lives, especially financially. In fact, I once met someone who could be said to have a poor financial situation. I asked the person about his desire to change his life. Then the answer that came out of that person, quite surprised me. Because he thought that he no longer had big hopes of being able to change his life. Even though this person could be said to be still young, it is certain that he still has strength and is physically strong. But maybe because his thinking and mentality are weak, he has thoughts like that.

So in conclusion it is very clear, that if we want to become rich, then we have to start from within ourselves. Because as you said, the biggest cause of poverty comes from oneself. So in essence we must continue to have strong desires, beliefs and motivation.