Often when a campaign is scheduled, it will be configured to run on a date/time in the future. During the time between when the campaign is initiated, and when it is actually scheduled to send, it’s possible for the number of customers eligible to be spoken with to change. Some of the factors causing this include customers choosing to opt out of communication or being communicated with too many times during a given period of time. As a result of these factors, the number of customers actually enrolled to a campaign is often lower than the Maximum Customers configured.