n. The tendency to make errors on a device where the keys or screen elements are too small.
2011
The most striking observation from testing the Fire is that everything is much too small on the screen, leading to frequent tap errors and accidental activation. You haven't seen the fat-finger problem in its full glory until you've watched users struggle to touch things on the Fire.
2011
Sizable erase and undo buttons at the bottom of the screen let you fix mistakes easily. Nevertheless, anyone who suffers from the so-called "fat-finger" problem or has stiff or arthritic hands should approach the game with an ounce of patience.
2000 (earliest)
I really need to get this fat finger problem checked by a doctor, or get a bigger keyboard for my laptop!
This is what I call the fat finger factor — while editing any configuration file (no matter how benign your changes are), you might introduce a stray character or two that makes a key command or parameter unintelligible to the server.