There are several benefits to defining quotas. You can use the default, explicit, derived, and tracking quotas to manage disk usage in the most efficient manner.

You can limit the amount of disk space or the number of files used by a user or group or contained in a qtree.

The amount of disk space or number of files used by a user, group, or qtree can be tracked without imposing a limit.

Notifications can be generated when resource usage reaches specific levels. This warns users when their disk or file usage is too high.