The simplicity of the Apple UI has its merits, but there are a few major issues that have historically plagued the Mac OS and which deter from an otherwise enduring and endearing human-computer interaction.

1) Persistent Application Modes

The Mac OS, unlike Windows or Linux, has a UI hierarchy: System -> applications -> windows. Thus the user is always in one particular application mode, whereas in alternative OSes, the application and window are combined. The main point here is not to discuss which theory is better, rather to point out that the Mac’s application modes are fine, as long as the mode travels with the focus of the user. e.g., say I have a Finder window open and am browsing files, but I quickly want to check the weather in my browser. I open a browser window, thus switching to “Safari mode”, proceed to check the weather, and subsequently close the window, wishing to return to my Finder browsing. Aha! As I press a hot key combo specific to the finder, I realize by looking at my menu bar that I am still in the Safari mode! I need to switch applications to return to Finder mode. This is consistently annoying behavior. The mode should travel with the focus.

Unfortunately the solution isn’t as simple as Apple allowing the user to choose which method to use say in a Preference Pane, because this is a fundamental aspect of the Mac UI. While it is slightly more confusing to have this occur when multiple Safari windows are open, as in the above example, it would be consistent at least to switch applications if the user closes the last window of the application currently in focus.

2) Dock applications

The loading and unloading of applications to/from memory should be invisible to the user. Apple’s progress in this area has come a long way, however there is one horrible inconsistency with respect to applications permanently in the dock: without loading an application the user is unable to view or utilize the sub-menu features of the application, when he right-clicks on the app icon. The best example of this is the System Preferences Application, which when loaded, lets you select the particular pref of choice through the dock sub-menu. However you cannot keep this app loaded without the window actually showing (or minimized). Thus when you would actually want to use the dock menu (that is when the main prefs window is not on-screen), you cannot use it because the app isn’t loaded!

3) Integrate Finder and Safari. Come on. Column web browsing would be fantastic.