If you have implemented your CRM organization and not done a sanity check of the built-in cascading relationships for the COLAC (contact, opportunity, lead, account, case) entities vs. your corporate business practices then you have missed an important step in the architecture process.

When you have a one-to-many relationship there are effects to the related entity when you make changes to the parent record. These changes impact ownership, record status/state, and access rights. You can accept the out of the box behavior or you can customize it to fit the way your organization works. For example when ownership of an Account record is assigned to another CRM user, who should own all the open and closed – activities, opportunities, cases, etc? This can have significant impact on performance tracking, access to records and customer insight.

The MSDN system has a good technical article on this subject. And although this link references CRM 2011 it is equally applicable to CRM 2013.

http://msdn.microsoft.com/en-us/library/gg309412.aspx

Dynamics CRM Entity Cascading Relationship