A minute is exactly 60 seconds

[dgp1130]

False. This is more of an implementation fallacy, but I figured I'd share it anyways (up to you if it fits).

https://en.m.wikipedia.org/wiki/Leap_second#:~:text=Implementation%20differences,-This%20section%20needs&text=Not%20all%20clocks%20implement%20leap,servers%20declare%20%22alarm%20condition%22.

The implementation of leap seconds varies across systems. Some add an extra second to 23:59. This means that 23:59 has 61 seconds to include the leap second. It also means that 23:60 is a valid, displayable clock time.

You can also have a second fallacy: "A second is exactly 1000 milliseconds". This is also false, as some implementations will freeze or slow the passage of time for 23:59 to include the leap second, making it take 2000 milliseconds to pass. This avoids the previous problem but also means that setting a timer for 5 seconds at this moment would actually take 6 real-time seconds to go off.