The purpose of regular trademark monitoring is to ensure that third parties do not apply for and register comparable trademarks that could be confused with the already registered trademark and therefore conflict with it. After publication of the newly filed trademark, the owners of the earlier trademarks have the right to file an opposition against the registration.
Just like trademark monitoring, the registered design should be reviewed at certain intervals. Here, too, the purpose is to immediately prevent infringements of the registered design or to exclude further registrations of comparable designs.