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that's what wage labor is. Under capitalism you must become one or starve.

This book explains it well.
https://www.marxists.org/archive/marx/works/1847/wage-labour/

Wages are an exchange of value. In fact, wages and debt must be paid BEFORE there can be any retained earnings. This is why being an entrepreneur is burdened with high risks.

ah yes that's why statistically they always win, like a casino.

"Wages are an exchange of value" The upkeep cost of the worker is that exact value. Feeding a slave is an exchange of value, paying your wage laborer just enough to survive is the exact thing.