Associate Burnout

I did a search on this but was not really able to find a clear answer. I know most of the posts on this site a geared towards Analysts who are mostly in it for 2/3 years and then use the experience as leverage into something better. I am someone with only a military background who is looking at Banking as a permanent career change . I have a question that is difficult for me to get a hold on:

On average for BB firms, what % of associates actually move on to VP and MD? Of the ones who don't make it to that level, are they usually asked to leave due to poor performance, or do most leave on their own to do something else because they don't like the life of Banking?

I know job security isn't exactly a strong point in the wall street career fields, but I would just like to know what I would be getting myself into if I did decide to leave the Air Force for an MBA. My final goal is to land a FT job as a career-changing associate (I know, every analysts' worst nightmare).