Message Oracle QSM-01222 - materialized view string is less optimal than string

ERRORmaterialized view string is less optimal than string
CAUSEQuery Rewrite always chooses the most optimal materialized view based on certain parameters, such as cardinality of the materialized view, number of joins etc. The materialized view specified was found to be less optimal.
ACTIONTo force using a materialized view, consider using a rewrite hint.