Deals that have not been acted upon for a number of days are termed as rotten deals. You can set how many days of inactivity you can tolerate on a deal. This number of days is specific only to a stage in a pipeline. The deals bearing a orange mark and a number on the top right are the ones which are rotten.
1. In the CRM module, admins can see a Gear icon on the top right corner. Click on it.