Someone (Joel Spolsky?) wrote that you should never disable a menu item. At the time, I thought he was just being a puritan, but just recently I, too, have become a subscriber to the idea.
Last night I was up until after 2am playing Spore — I progressed my horribly disfigured shark-wasp into the space age, and had begun the initial process of colonising nearby planets. Then, at about the time my wife wanted me to shut off the computer, I realised — I couldn't save my game! I tried all the apparently logical things: I completed (or abandoned) all my pending missions; I returned to my home planet again and again; I hovered over all the cities; I searched the menus; I did everything I could think of until eventually I got sick of seeing that greyed-out "Save" menu item, with no explanation of what to do to make it not-grey. So I prayed for an auto-save at the civisilisation-to-space changeover, and exited the game without saving.
Today I discovered that, in fact, the last time the game's progress had been saved was when I did it manually towards the end of the civilisation level. I'd lost the end of my cilivisation phase, my beautiful space ship, and the planets I'd been exploring and working on. I basically had to start over; which I did, mind you, at full force. (The new space ship is much scarier looking than the old one.. I think, although I can't exactly remember it.)
The other thing I discovered today, since I had time to explore the system, was that during the space phase you can save while in orbit around a planet, not inside its atmosphere. I don't recall seeing that written anywhere — most significantly, nothing at the game's main menu even hinted that, for example, "You can't save while inside a planet's atmosphere." All I had to go on was a greyed-out "Save" option.
At least they could have had a useful tool-tip. Even better, they could have discoloured (but not disabled) the menu item, and changed its behaviour to display a dialog explaining why I can't save at this particular juncture. Turning the menu item off without offering the slightest hint as to why, or what to do to get it back, is just infuriating for the user. I didn't care what technical reason there was for it — it's bad enough that as soon as a level transition occurs you have to sit through the whole "design your new whatever" process without the ability to save it for later; but I can understand that one. But why the hell I couldn't save my game, even after trying to address all the technical issues I could imagine, was purely aggravating.
Since being on the receiving end of this nastiness, I'll endeavour to not make the same mistake with any user interfaces I end up designing in future.
P.S. somewhat relatedly: the other day I worked out how to sync Media Player and my wife's PDA. Even using ActiveSync it was tortuous. The tips about what to do in Media Player — the tips inside Media Player — were wrong, or at least referred to menus and items that Media Player didn't have. No wonder Apple blows them away with a couple of gimicky UI features and a bit of polish. Microsoft's user interface really sucks.
... Matty /<