If you are a system administrator, you will want to have a way to monitor quotas to ensure that they are not being exceeded. An easy way to do this is to use warnquota. The warnquota command sends e-mail to users who have exceeded their soft limit. Typically warnquota is run as a cron-job.

When a user exceeds their soft limit, the grace column in the output from the quota command will indicate the grace period -- how long before the soft limit is enforced for that filesystem.

Disk quotas for user jane (uid 1003): 
    Filesystem  blocks   quota   limit   grace   files   quota   limit   grace
    /dev/hdc1   10800*  10000   11500    7days      7     2000    2500

By default, the grace period for blocks and inodes is 7 days.