Hi @Younguru,
The late registration depends on lots of things, stake usually but they are not all the same because of variation. Sometimes there are rebuys too.
To quote Rob, our Operations Manager, Consistency is important because people like to know what to expect, but variety is vital too. Not all 20,000 entry tournaments should have the same period of late registration, else it becomes too stale.
I want to suggest reading this post about this topic, as players shared their insights about Late registration.