Is Poverty Neccessary?

If we ask anybody that "is poverty necessary?" they will answer no. They will probably argues that poverty can't be necessary. If I am asked this question before, I used to say the same answer. But after reading Marshall text, my opinions have changed. When we think in logic, we understand that poverty can be necessary. Because there's no way everybody's equal. If everybody have same income, nobody wants to do bad jobs like cleaning toilets, there are no competition in workers. An economic institution can't be equal because of its nature. Even if we dream a world that everbody are equal it is impossible to come true.