I used to have an alarm clock app that would require you to solve an arithmetic problem before it would shut off. Obviously, to solve the problem, you had to type in a number; as such, when it went off, it would turn on the display with a numpad visible.

Very frequently, it would go off, but I wouldn’t fully wake up and, seeing the numpad, would think I was in the middle of dialing a phone number.

Trying to finish a number I never started rarely worked.