Trivia: Jim Henson was incredibly disheartened by the critical backlash against the film (mainly aimed at its frightening imagery and simplistic story) and its failure at the box office, and it left him greatly depressed. However, shortly before he died, his son told him that the film was finally finding a strong and dedicated cult-audience thanks to its home-video releases, finally fulfilling the potential he initially saw in the film and giving him a sense of peace regarding the film. The film has since gone on to become more and more popular in the ensuing years, and is now considered something of an "80's classic" and to this day is still a hot seller on DVD and Blu-Ray.
Trivia: The film is called Labyrinth, but it is about a maze. A maze and a labyrinth are 2 different things. A labyrinth has only one path, leading to the centre, whereas, a maze has multiple paths which branch off, and may not lead to the centre.
Answer: To add to that, the other door was supposed to lead her to certain death, and technically the oubliette wasn't exactly certain death.