Lester C. Thurow wrote about The Zero-Sum Society back in the 80's. Income grows (generally) over time, but at any one time it is a fixed amount. For some people to get way, way more than the average income, others will have to receive much less than the average. Much of that process takes place in businesses, where self-interested individuals get to decide what the distribution of remuneration in the business will be: the less some are paid, the more there will be for those in positions of power in the organization. Add to that 'it takes money to make money', and the system propagates and perpetuates and a massively skewed distribution of income.

As it happens, I have developed a way to eliminate poverty by eliminating the zero-sum character of income. Higher incomes are unaffected (there is no redistribution), but the money for a minimum guaranteed income is created as needed. The amount of the income is based on the current median (or perhaps average) personal income — so in the U.S., at least $15/hr.; $600/wk. The income would not be paid to everyone, but any adult citizen could become eligible for it. If curious: "Same Economy, Way Better Outcomes for Society" here in Medium