Setup and Customization Views in the Personal Account Review
This metric is included to help you find ways to improve your Salesforce organization. Setup and Customization Views is a good approximate measure of how much customization is done inside your app this month.

The most successful Salesforce implementations are customized to match the business processes in your organization so that the application works the same way your company works. In the initial phases of Salesforce you would expect this number to be relatively high, indicating that users are setting their preferences and customizing the app to their liking. Over time, this customization will drop off. If you’re having trouble getting users to adopt Salesforce, check out the page views in customization. If they’re low, try finding ways to customize the application to your business processes.