The number of complaints helps to provide you with information about user satisfaction without the cost of customer surveys. In smaller organizations, it may be more useful to discuss each individual complaint in team meetings, but in larger organizations with a large user base, this metric can be very useful.

The metric has to be measured against the total number of users. So what you want to know is the average number of complaints per user:

This should normally give you a low number if your service is good. If you measure this over the period of a year and get a number of 0.5 that means you have a complaint on every two users on average. Whether this is a good number or not completely depends on factors such as: the type of your organization, the complexity of your product or service, the expectations of your users and the level of dependency of your users on your product or service. Use this tool for trend analysis mostly. If you look at the twelve months in a year and see a spike in this number in a particular month you may want to research what happened in that month. Was there a new release with related problems? Did your help desk have capacity problems? Was there some marketing action to draw in new users, raising expectations too high?