Hard and soft quota limits
There are two kinds of quota limits provided by WinQuota: "soft" limits and "hard" limits.
Hard quota limits
Your settings will not be exceeded at any time; just specify hard limits for directories you need to manage precisely, and let WinQuota work. Users will not be able to increase, exceed or cancel quota settings by any kind of operation they might undertake. Logically hard quota limits are the same as physical drive capacity limits.
Soft quota limits
To track the usage statistics, provide quota settings audit or just to keep Users expectations soft quota limits can be used. Just as for hard quotas every attempt to exceed soft quota limits will be tracked precisely. User's actions will be limited by hard limits as usual but every soft limit exceeding will be reported to you without User notification.
There is a possibility to determine custom scripts and 3rd party programs that can be used as soft quota excess triggers. Thus it can be any action you prefer, for example, inform User via email, collect information into database, notify Administrator via pager/SMS etc.