I thought the same thing about OS X’s “inability” to maximize windows. The more I used the OS, though, the more I came to the understanding that maximizing the window, or attempting to maximize the window, is most often counterintuitive to the workflow of the system.
The Human Interface Guidelines that developers are supposed to follow (along with Apple, for the most part) advise the developer against maximizing the window. Instead, they recommend that the most sensible size for the application window be selected by the developer.
In addition, the app is supposed to remember the user setting that you gave it, to a certain degree; except for what amounts to the heavy-duty apps, no window really has much business taking up the whole space, so the zoom button will use a size that better fits the screen, should you set the window to the whole screen.
It’s not Apple per se, but the developers who don’t “support” full screen in their app (just take a look at a pro-app, such as Final cut, if you want to see an example of an app that really ought to be full screen).
The system is actually quite helpful. For example, when working cross-Adobe CS app (zB Photoshop, Illustrator), you will note that the windows of both apps can be side-by-side, instead of contained in a parent window. This allows you to more-seamlessly work with the applications together, rather than in a walled garden approach that you will find on the windows side of the pond. The tendency to leave a window unminimized
gives you the freedom to work on multiple docs side-by side… Copy and paste becomes a whole lot easier when you don’t have to toggle foreground apps nearly as often.
OS X is not Windows, and while the concept of the window itself is not lost on the OS, the manipulation of windows differs a lot from Windows on OS X. It’s not nessesarily bad, just different. Give it a chance! It may seem annoying now, but when you begin to utilize the cross-window usage abilities of the OS, you will gain an appreciation for the multi-window layout. Just try to keep an open mind…