- Many - my bowl is full and I cannot see the bottom
- Some - the bottom of my bowl is covered with little plastic showing
- Few or none - I can see most of the bottom of my bowl, and I don't care if there's some round the rim MeeOW!
This of course is good enough for a cat - it knows if it has enough in its bowl and can go and do cat things or if it has to find a human and annoy the hell out of them by scratching the fridge, study chairs, walking on keyboards while you're working, and the like, to get them to add content to the foodbowl.
Fine, enough cat stories, why are you writing about this?
Simple answer - user interface design and changing user expectations of the interface.
Looking at less technical users using applications such as Skype I've noticed a similar phenomenon to the cat and its bowl. They see the nice pane in the middle of the screen and can happily use it to call people, use the dialpad etc. What they can't do is navigate the pull down menus to add a new user - they need someone to help them.
Interestingly they seem to focus on the pane and (on a Mac at least) don't perceive the menu bar along the top of the screen, ie they focus on the application pane. Not a problem for full screen applications, but a problem for other applications.
Now this is purely anecdotal, and I havn't seen it in Windows or Linux (Gnome or KDE) users, but I wonder if we're seeing an iPhone/iPad one app/one screen type of effect here on user expectations ...