Daniel Grant describes the relationship between Jackson Pollock and his dealer in terms that bring to mind sharecropping where, if the farmer fell behind in the value of his output, he built up debts that bound him to the land. Here, if Pollock did not cover the cost of his stipend in sales he had to make up the rest in work:

When Jackson Pollock signed his first contract with collector and dealer Peggy Guggenheim in 1943, he was able to quit his job decorating ties to concentrate on painting. That first contract paid him a stipend of $150 per month, with guaranteed sales of $2,700 annually (if there were less than $2,700 in sales, Guggenheim would be paid the difference in paintings). His second contract with her two years later raised the stipend to $300 per month and gave Guggenheim ownership of Pollock’s entire artistic output for the year with the exception of one painting that the artist could retain. The terms of those contracts might not satisfy artists nowadays, but it was beneficial to both Pollock and Guggenheim then, reflecting her trust in his talents and allowing him to work unencumbered by financial constraints. This was a true partnership.

Like It or Not, Artists Are Married to Their Dealers (Huffington Post)