Which Clock Works Best The One That Loses
Riddle: Which clock works best, the one that loses a minute a day, or the one that doesn't work at all?
Answer: The one that doesn't work is best. It will always be correct twice a day, but the one that loses a minute a day will not be correct again for 720 days (losing 720 minutes or 12 hours).
Source: https://riddles.com/112
