Development Hell: The game that got released was actually the third version of The Dig that LucasArts had worked on. The earlier two iterations of the project never got finished due to assorted difficulties in development. All told, about five years elapsed from the initial game idea pitch by Steven Spielberg to the release of the final Dig. Not unusual for today's market, but a lot at the time.
What Could Have Been: Spielberg originally imagined the story for live action television, then as a film he would have made with George Lucas, but it would have been far too difficult and expensive to portray the story via live action and CGI so he proposed it as a video game. The idea of making it into a film has never been officially shot down, but it hasn't gone forward at all either.