It is the most important company in their portfolio and they are afraid that should their investment in Uber not payoff int he most spectacular fashion, they th

It is the most important company in their portfolio and they are afraid that should their investment in Uber not payoff int he most spectacular fashion, they themselves would find out just how difficult it is to raise money after being labeled as a failure. [edit: Payoff in a most spectacular fashion here means "exited at nearly the top of the valuation"]