Why is time-counting in video players irregular?

How do you know they aren’t? What are you using to measure the duration of the seconds?

I use the same measure you are. And, silly you, I know because I see the seconds running.

If you are referencing countdowns/timers in video games, it might be irregular because they most likely didn’t use an actual clock to set the time. They probably used coding of some sort, and it could be at a slightly different speed than whatever you’re using to compare the time with (phone, watch, etc).

It could be they are “sampling the time” (displaying a change) in video not running an actual timer