Not caring shows toughness, in their minds.

“Welzer further describes that Nazism even managed to incorporate an individual’s struggle with deeds into their frame of reference. They knew that what they were doing was immoral on some level but it was framed in a way where an individual who struggled with what they had to do and did it anyway was perceived as a “real man” because he would put the good of the people’s community over his own feelings.”

https://www.reddit.com/r/AskHistorians/comments/8si6x5/monda...