Most digital alarm clocks have a pretty simple interface with one button for hours and one button for minutes. You set the alarm time by pressing a ‘set alarm’ button simultaneously with the hour or minutes button and cycle through the numbers. The problem is that if you want to change the alarm from say 7:20 to 7:10 you have to cycle 50 minutes forward, which takes about half a minute of keeping two buttons pressed as you watch the minutes go by. Either that or rapidly press the button 50 times, which may be a little faster.
So, deep question: how many people set their alarm clock to a time that’s not a multiple of 5 minutes? Setting the alarm would be much easier if the minutes just incremented by 5 each time. And it would prevent the ocd issue of just missing 7:10 and stopping at 7:11 after which you’d have to do another round.