If the company makes money, there is very little reason to fire the CEO. In fact pretty much the opposite, there are probably CEOs that would deserve to be fired for multiple reasons, but because the company makes good money, the board won't care. The board is responsible towards the owners, if they actually fire a CEO of a performant company, they really have to show why it was in the best interest of the owner.

All these stories where the CEOs were fired are from companies that weren't profitable, needed constant funding rounds etc. In the situation where the company is just sucking money from investors the CEO gets changed easily.