The Seven Dwarfs

The Seven Dwarfs was a proposed prequel to the Disney animated film Snow White and the Seven Dwarfs.

Plot
Originally, the story was pitched explaining how the Dwarfs met, and how the Evil Queen killed Snow White's father and took the throne. However, it was later changed to center around Dopey and how he lost his voice upon witnessing his mother's death.

Why It Was Cancelled
John Lasseter became CEO of Disney and all direct to DVD sequels or prequels were permanently cancelled following his appointment to chief of the company.

Result
It remained shelved and will likely remain so from now on