Reason: For support of multiple security domains and automated distribution of certificates it becomes tedious and error prone to configure each application to skip or perform checks for revoked application certififcates and or revoked issuer certificates. Please note that some security domains may choose not to use CRLs at all but use short lived certificates instead. The Certificate Authority knows which checks to perform and which checks to skip. So a Certificate Management could distribute that information as well.
Please note that some Certificate Authorities might even choose to raise availability over security with regards to some aspects and thus want to even have the check for the validity period of certificates disabled.