The Amputee exists because the years long production of Eraserhead-David Lynch's first feature length film-ran out of money and had to shut down. The American Film Institute-which was helping to produce Eraserhead-was looking to test two kinds of film stock. David Lynch and his collaborator Catherine Coulson (known in later years for playing The Log Lady on Twin Peaks) wrote a script overnight, and had Frederick Elmes-the director of photography on Eraserhead-shoot it as one scene, all in one take for each version, shot on the two different film stocks.
So, The Amputee was created to scratch an itch: the desire to create, even in circumstances where there's no money, no real crew, and a script conjured from thin air.
What's possible?
How much something can you get from nothing?