Having worked at Yahoo a few times ...

The press usually reports senior executives leaving as constituting a "brain drain." But if even the CEO's are worthless, as the last 5 have been, how can the senior executives be expected to have any brains?

The real Yahoo brain drain is the loss of experienced engineers. And since option blocks are no longer offered to engineers, nobody with any experience is going to join.

The only people left are long-time employees with old option grants, recent grads who got rejected from Facebook, and H1B's by the thousands.