Direct-to-video releases have historically carried a stigma of lower technical or artistic quality than theatrical releases. Some studio movies released direct-to-video are movies which have been completed but were never released. This delay often occurs when a studio doubts a movie's commercial prospects would justify a full cinema release, or because its "release window" has closed. A release window refers to a timely trend or personality, and missing that window of opportunity means a movie, possibly rushed into production, failed to release before the trend faded. In movie industry slang such movies are referred to as having been "vaulted."