Hello Vinoth,
more security because it provides a way to control from what IP subnets the new IP subnet for management can be accessed.
For example end users from client vlans shouldn't be allowed.
An insider attack from a client vlan is more difficult if the switch ip address is in a different vlan.
More resiliency: if a broadcast storm occurs in the client vlans having a separate management vlan helps and can make the difference between being still able to access your switches or not.
And last but no least the management vlan shouldn't be the default vlan1 but a different dedicated one
Hope to help
Giuseppe
