Because growth is now baked into the share price. If they don't keep stoking the fire of optimism, it burns out and the share price collapses. Our current business culture is saying that this is what managers need to think about, so this is what they think about.

I would be happy with a vast economy of Mittelstand type businesses, each producing ball bearings or gear wheels, not trying to eat the whole planet, just existing at a sensible level. It's not like they can't grow if the opportunity arises.