Maybe. It could well just be the market and luck, but it could be the CEOs decision. On the other hand, it's never because the line workers just started working harder. Think about being an early engineer at Amazon vs the same at another startup that never went anywhere. Those engineers did the same amount of work, but the difference is that Jeff Bezos was telling the Amazon engineers what to build. BTW I'm not making an argument that workers shouldn't share in the gains, just that people at the top are much more likely to be responsible for them.