Original: As the DVD format supplanted the videocassette, companies released movies in DVD format rather than VHS, causing the term "direct-to-DVD" to replace "direct-to-video" in some instances.
Simplified: As the DVD format supplants the videocassette, companies have increasingly released movies in DVD format rather than VHS, causing the term "direct-to-DVD" to replace "direct-to-video" in some instances.