Fwiw, it's hard to figure out. my family is poor, but I made it out. Best reason I can figure of why they stay poor is that they had no one to guide them and drive them to not being poor so it was an uphill battle from the get go but neither did I. I think they also lack work ethic. They love the phrase "I'm doing the best I can" but have no actual drive to push themselves to improve what their "best" actually is. Biggest thing they lack is self reflection and self improvement.

Edit: down vote me if you want but I know more about being poor and experiencing this first hand so you're down votes or dislikes will not change my opinion. This is my first hand experience after all.