Why no. of VLANs allowed on a switch is 4096 which is huge compared to the maximum possibility of VLANs which will actually work at a time on a 24 port switch can be up to 24 only (if we have each port in a different VLAN).

One reason could be for future use but 4096 port switch is hard to see in future.

I think I am lacking some basic concept here.