No easy way to maximize window and full screen mode weirded me out. On Windows, I’d just double click on the window title. But on Macs, I had to carefully hit the green plus button.
I'm a Windows refugee who made the switch in 2006 and I'm very happy with my Mac, but I still can't wrap my head around the behavior of this button. There doesn't seem to be any method to its madness. Clicking it consistently results in the window's size being altered somehow, but I've never really understood how OS X decides what dimensions to resize to.
When I switched to Macs, I abandoned the concept of toggling maximization state altogether. Each window gets a workspace, and four fingers in a direction takes me back and forth, or shows me all windows. No toggling, no alt-tabbing, etc. I find this excessively more convenient, but as usual, YMMV.
P.S. I do agree the + button has absolutely inane behavior. I just like the workspace method more than I ever liked toggling maximization state, moving windows, and alt-tabbing.
I kind of feel like this is where OS X is almost at a moment of brilliance, but hasn't quite reach there yet (and is hampered a bit by legacy considerations)...on just a single screen, full-screen mode works almost exactly like you describe and is a joy to use.
You want to know what the Zoom button (the green one) does? Here's what it does: it toggles between user-managed size and app-managed size, where the user-managed size is the size that you last resized it to, and app-managed size is the size that the app thinks is the optimum size for the window's contents.
Did you understand all that? Yeah, it's not easy. Now you'll see why many developers simply give up, have it fill the screen, and cause people to call it the 'maximise' button instead.
As an example, as I click the button in the BBEdit window I'm typing this comment in, it resizes to take up the entire screen vertically (because you need lots of vertical space for coding), but only enough horizontal space to hold the sidebar and 80 characters of text (it depends on where you have your wrap margin set). It doesn't resize to lose any content out the window, it resizes to the optimum size. If I click it again, it resizes to the size I last manually set it to.
Honestly, I'm not sure quite why Apple added it in the first place, other than to have an aesthetically-pleasing three buttons: I use it rarely, much less often than maximising something in Windows. And it confuses people.
It's the "zoom" button, and it's supposed to toggle between two sizes: user state (whatever you last dragged the window borders to be), and standard state (whatever the application thinks makes sense for the window's content [1].
This works for applications where the content has a natural fixed size (for example, Photoshop snaps the window to the size of the image), but breaks down for flexible content (web browsers, terminal windows, etc.). Also, it's up to application developers to get this right, which isn't always the case.
Except Apple's own iTunes. I know it's a mess of an app to start with, but for iTunes 10 or earlier, the green button used to throw it into mini player mode. Now, it maximizes/restores the window, ignoring the content dimensions. And not to be confused with full screen.
I only recently made the switch and I'm very pleased as well. I had the same thoughts as you for a while, but i recently started using slate, (tiling window manager) and I never think about clicking the plus and that, ctrl+cmd+space to full-screen a window, and I have bindings for lots of configurations. Never even use the trackpad for window-manipulation anymore, fantastic productivity booster.
I'm a Windows refugee who made the switch in 2006 and I'm very happy with my Mac, but I still can't wrap my head around the behavior of this button. There doesn't seem to be any method to its madness. Clicking it consistently results in the window's size being altered somehow, but I've never really understood how OS X decides what dimensions to resize to.