Data decay
The gradual loss of accuracy of CRM data over time, as people change jobs, companies change and records stop being updated.
A record is accurate on the day it's created. After that, the contact may leave the company, change phone number or get a new title, and the company may move to a new domain or be acquired.
Decay can't be stopped, only measured and corrected: by auditing the CRM regularly, enriching records from up-to-date sources and making key fields required where data enters the CRM.