The many scenes of the holocaust are vivid and compelling, and continue to appear afresh in print, the horror undiminished over time. The holocaust horrors are likewise well documented, as where millions of neighbors are dragged off there are likewise millions of neighbors left behind to remember the circumstances. And where numerous gas chambers and concentration camps have train loads of hollow eyed and stick starved Jews moving toward the gas chambers and only the smoky smell of death and piles of gold fillings jerked from the teeth of the dead emerging from the camps, there can scarcely be any doubt as to the activity going on. However, the fact that the holocaust is vivid and well documented is one of the reasons for a holocaust denial.
In short, the more horrible the event, the more guilt one bears toward this or similar situations, the more likely denial will be used to deal with the discomfort the event engenders. Denial of horrific events is so common as to be almost an everyday event in human lives. The ease with which the conscious mind of humans can sever memories so the mental pathways are not traveled readily adds to this, as it is a ready route to be taken by those who want to forget or put an alternate story into place. Those responsible for an accident begin to think that the victim himself caused it, thus relieving themselves of responsibility. Those responsible for a crime likewise excuse themselves by blaming the victim.
This tendency is one reason the most heinous crimes, such as the mass rape of a young girl, can be turned around to be her responsibility. She was flirtatious, and brought it all down upon herself. By this all men who turned an eye toward a vulnerable girl and pondered having her in a helpless state are relieved of responsibility for the acts that such thoughts might engender. They tell themselves that they are not the perpetrators, even in their thoughts, as the victim was guilty. Likewise the holocaust is often explained away as something the Jews brought down upon themselves, due to being financially and professionally successful. Then engendered jealously, so they had it coming to them! If this does not fly as an excuse, then the holocaust never happened. Those wishing to deny that thoughts can turn into action, and that they share the thoughts that the perpetrators held, will even cling to the absurd rather than discomfit themselves.