With its science-fictional premise, this episode would have been more appropriate for The Twilight Zone series. At the same time, though, its macabreness makes its appropriate for Hitchcock. And an exceptional story at that.
What makes it exceptional is that it also ventures a social commentary on a somewhat taboo subject, that of Assisted-Suicide, controversial Euthanasia. Many years after this episode was aired, the controversy of Euthansia would get Real-life national attention by way of Doctor Jack Kevorkian. People with agonizing terminal illnesses would go to Dr. Kevorkian to request a peaceful and painless death which the Doctor would provide with his Suicide-Machine. This stirred a flurry of controversy on the subject of Assisted-Suicide.
In the Hitchcock episode, we see that the Main-Character is a failure at even his own suicide, which is why he seeks the services of the Thanatos Palace Hotel. Even in Real life, we see instances of people whose Suicide-attempts BACKFIRE, so that their botched attempt leaves them in an even WORSE state than before. For example, a self-inflicted gunshot to the head can result in the person still surviving but now with severe brain damage so that his whole body has become paralyzed. Even an overdose of sleeping pills can cause severe damage with its poisonous effect. This is why the idea of Hitchcock's Thanatos Hotel seems so attractive and even humanitarian. For myself, being at the age that I am, I worry about agonizing illnesses, so I often wish that Hitchcock's Thanatos Hotel could be a reality. Macabre as it is, the idea is actually humanitarian.