As someone who's run both an egalitarian non-profit and been involved in a highly-effective corporate:
Egalitarian non-profits often struggle to achieve their goals because...
1) The profit motive is an enormously useful tool to focus efforts and determine if given actions are effective or ineffective. When you deliver a product or service that people pay for you know you've created real value. Money is value exchanged for value.
2) Egalitarianism doesn't work when you're trying to deliver disruptive change in the form of products and services. Hierarchy is required to make decisions, make tradeoffs, hold people accountable, and more.