100% correct @LN
In reality many minor changes don't have an explanation given either; i.e if I cross out age 8 and put 9 (or even say 20 and put 40) I might well just initial & date-time.
That is to say that ideally there needs to be an option to record changes but its not compulsory to do so (but it is compulsory to date & identify who made the change)