It’s a fairly common practice for companies to provide a window of time when a service will be performed. This practice can be applied to a diverse set of tasks, whether it’s repairing an air conditioner or performing scheduled maintenance on a website. In each case, the goal is to tell customers how long the service will take so they can plan accordingly.

But sometimes this concept gets taken too far. For instance, a company might provide an eight hour maintenance window for a service that should only require one hour, to cover the rare case where their staff gets delayed. While the window would technically be accurate, it makes the customer view the company as disorganized and poorly managed, since they can’t even pare things down to a reasonable timeframe. Worse, customers who are unfamiliar with the work to be performed might think that it’s really complex, and they get anxious about living without the product or service for the whole day.

In these cases, the best approach is to provide a reasonable window that captures 95% of cases. Then, make sure there is a process in place to notify customers if things are running behind schedule. That way, people don’t have to waste their whole day waiting around — or get needlessly worried — when there’s a really good chance the technician will show up in a much smaller and more logical window.