Record time in OTB tournament?

Iam just curious, i saw a bunch of players record the time of each move during OTB games. Any mean behind this?

For me, it's part of diagnosing and treating time management problems, such as taking too much time in game phases or situations.

Some people may rush, but that's not my issue.

yes i like to record the time every 5-10 moves just so it shows the gradual time difference. Shows places you spend lots of time on moves and when you didnt. Also shows when you get into time trouble so it can show the route of error. If you have 5 mins and your opponent 40mins you will be moving much faster. if you dont record the time you would not know this unless you remember but who is gona remember all their games.

I didnt think about this. Thanks