When looking into libraries to make my programming life a little bit easier I've (almost) always been disappointed by the prices offered. For instance, Actipro's WPF Studio is $650. I suppose that's worth it if you plan to make money from the use of those controls. But take a look at, say, Windows. Windows 7 Ultimate is just about $220.

I consider Windows to be a far more complex and "worth-it" product/purchase than a library that runs on it. Why the significant difference in pricing? Do libraries really need to be so expensive, or do they need to charge more in order to make a decent some of money?