SugarSync, a well liked Dropbox competitor, announce it would no longer offer a free pricing plan.  Josh Gans says all the usual things over here, plus one more thing:

That said, it is hard to see this move as a positive one for the company. One of the things I worry about with backup services is that they will always be there when I need them. But the worry is that the company may go under. This move from SugarSync does not inspire confidence in this regard. It is suggestive of a company under pressure and looking to a possible change in industry practices to keep it going.

It’s true.  You appear mean, desperate and weak If you don’t give a lot.  That’s not an industry practice, it’s a universal.  The details vary.