Designed for Use, 2nd Edition

Small Targets Need Margins

Since smaller targets are harder to hit, it’s very important that you put margins between small targets. Otherwise, a user may miss the correct target and accidentally trigger a wrong action.

In a way, this also applies to keyboard shortcuts. Assigning destructive and nondestructive keyboard shortcuts to letters that are right next to each other on the keyboard makes it more likely that people will initiate a destructive command by accident.