From a technology usability perspective, you can’t do much worse than make your users feel they’ve lost control. It’s maddening (and a bit frightening, if we admit it) to feel that “the computer” is doing things without your consent. We’re tolerant to allowing actions we don’t understand (after all, not everyone should be a technologist or a computer scientist), but we always want to have the kill switch at hand.
End-user operating systems (Windows, MacOS, GNU/Linux desktop environments etc) always have such a kill switch – it’s usually something red and obvious on every window (like the big “X” in the red box at the top right corner in Windows XP/7). If you don’t like what it’s doing, you have the power to kill it. Why? Because it’s your computer, dammit, and you should have the final word!
I stumbled upon an example of breaking this rule the other day, when I was helping a family member reinstall a computer that had bombed:
Here is a screenshot of the “Windows Genuine Advantage Notifications” tool (a propaganda term if there ever was one) installer: All application controls (back, next, cancel) have been disabled, and so has the omnipresent “X” that is supposed to offer users the warm & fuzzy feeling of control in every single Windows application.
Installers have for years now had ways of trapping window/application interrupt requests and responding to them gracefully.
Taking away control from the end user in such an obvious manner is both unsettling and frustrating.
A practice best avoided.