Well, that is a general question. This is due to the difficulty in the various economies and this applies not to every person or country. Also, greed is the cause of the issue as you see some people looting away the cash and heaping it up in their houses as they wish to save it for the future. The money to be produced by the Central Bank is calculated but when you embezzle that much money, those are to share in that cash won't get a thing so it leads to poverty.Even those that have it don't wish to bring it out or spend it as they think of the next day as they don't wish to be poor.
Read next
From @john-snow