Why did Yahoo! turn down Microsoft's purchase offer?

Realistically, though, whether the Yahoo managers and executives want Microsoft to take over their baby is irrelevant. Their first responsibility is to get the most money for the shareholders. So presumably they feel that they can either sell the company to someone else for more than the $33 a share Microsoft offered or they can remain independent but manage things better so that the market price rises above that. I doubt that they can do either.