It's not about changing the business model or culture. It's ensuring that the CEO can survive and has allies he can work with. I hate to break it to you, but

It's not about changing the business model or culture. It's ensuring that the CEO can survive and has allies he can work with. I hate to break it to you, but execs who come from the outside (i.e. non founders) rarely care about the long term future of the company. What do they care about? The stock options they were granted. The notch in their resume. And of course the money. Relatively short term plays. Surrounding themselves with familiar people cuts down on the tremendous political burden the job bears and allows them to get to those short term profits in an easier way.