Why try for a DBM position?
Because you don't work. You either babysit reps all day or make them miserable.
Because, there's no pressure, you just hope the numbers land your way. The reps are personally accountable for their numbers, docs, calls, and representing the company every day. Managers do nothing of consequence, except only to their minion reps.
The job is fantastic for those subhuman sciopath narcissists who can control, make miserable, and ruin good peoples' careers, maybe even lives. So for that sick bastard "JERK", the DM job is about as good as it gets.
If you are not an asshole, the DM job is a joke and so easy a monkey could do it. Ride with the reps 4 days a week and stay home the 5th. You can just ride along and watch, then you get to tell them what they did wrong or right in your eyes, the reps must kiss your ass and agree with everything to keep their jobs and hopefully get a star by their name come ACE review time.