RSUs are terrible for a private company that aspires to go public, because the moment they trigger -- usually IPO + enough volume traded -- the company owes half of them in taxes (regular income taxes). This places a considerable pressure on the stock and causes a crash on the price usually -- as everyone from peon to executive have to sell half of their multi-year "vestments." So instead of the company raising slowly money via the market and the employees getting a good check when they decide to slowly sell, Uncle Sam gets some taxes up front... (And usually due to the likely crash, less than they would.)