Companies reinvest earnings all the time. Some reinvest 100% of the profit they earn. Some reinvest a percentage, and then pay a dividend. If your question is: Why don't these organizations ever stay non-profit, then the answer is: They'd never have the funding to exist in the first place. If they were founded as a non-profit, they don't currently generate enough revenue to pay the cost of building and maintaining these models, so additional investment is needed. Investors want a return on their investment, so for-profit is the only path forward.