When a record is being updated or created, we place a lock on that record to prevent another operation from updating the record at the same time and causing inconsistencies on the data. These locks normally last for a few seconds and when the lock is released, other operations can do whatever processing they are supposed to do on the record in question. However, a given transaction can only wait a maximum of 10 seconds for a lock to be released, otherwise, it will time out.

Check the below link for more information

https://help.salesforce.com/articleView?id=000338933&type=1&mode=1