No dictatorship ever had a personnel shortage.
Some people once regarded an SS or NKVD uniform as a status symbol. The "bandwagon effect" where masses of people seek to follow the winner in a political contest can have special appeal if the winner leads the only political party and not showing an appropriate level of zeal can be lethal.
Once evil becomes bureaucratized, it is well on its way to becoming pervasive. After all, people have jobs and titles and are held accountable for making their little part of the machine hum. As with any job, there is paperwork and gossip and crazy supervisors. All they are supposed to do is to pay attention to their own area and obey. Oh yes, and believe. Asking larger questions is discouraged.
As a management consultant, I've long found the operation of dictatorships to be of interest. Nothing is more fascinating than how people who may be admirable as individuals can become monstrous when they are part of a group with evil values.