We all know that a second is 1/60 of a minute which is 1/60 of an hour which is 1/24 of an "average" day. That definition is stupid and arbitrary. It would make more sense to have a 10 hour day (no AM/PM) with 100 minutes per hour and 100 seconds per minute. There would be 100,000 seconds in a day versus the current 86,400, so a second would be slightly shorter. Unfortunately it will never happen because that would be a total change from what everyone is used to and basically every existing clock would be useless and have to be replaced.
Also, the calendar should be gutted and replaced with just the four seasons and days counting up to 91 or 92 each season.