The problem is clear, I think. But a simple example: You are an operator for e.g. a OBSD Firewall. Yesterday everything was ok, Today a person phoned me and want that I open a tcp port for him. Ok I open. Tomorrow, I notice problems that I never have had before. But I have forgotten the new open port. Now it is nice to have a ChangeLog.
Because it is faster than restore an Backup.
