According to my observations, most associates that enter IB post MBA have several characteristics in common. First, most of them went to crappy or semi-crappy schools for undergrad. In addition to that, they worked in some crappy jobs like HR/payroll analyst at the local office of a restaurant chain, loan administrator at some regional bank, or auditor at Big 4 at best. I think that many of them couldn't make it to IB after undergrad or didn't even try as they knew they didn't stand a chance. My impression is that they view their MBA and their IB gig as a chance to redeem themselves and put some 'prestigious' names on their resumes. It's not that I haven't seen post-MBA associates with impressive backgrounds, but these are not in the majority. Most associates I've seen are really mediocre. I also have the impression that most of these guys don't know exactly why they want to do banking, which is funny because they are supposed to be hired for the long term, but I don't think that most of them really have that intention, or even if they do, they don't know what they are getting into and soon bail out. Some stay because they don't know what else to do. Isn't that one of the reasons that you have so many bitter VP's and MD's who entered post-MBA and remained trapped with no good exit options and take out their insecurity for being mediocre on their underlings. I think the result is that one of the big differences between mid-level to senior folks on the buyside and sellside comes down to buyside folks being overachievers who managed to actually achieve what they wanted, while sellside associates, VP's and MD's being bitter and insecure as they failed to live up to their aspirations during their whole life, with IB being one of their biggest achievements. Seriously, the only reason that most of these people managed to get jobs in IB after MBA is that they face lower competition at that level as most analysts don't want to go back anyway.
Have you found these points to be true in your experience? As most of these people are not dead set on staying in banking, what is the point of going in if their exit options are reduced compared to those of the analysts? Most PE shops won't hire them,even less so, corpdev or are jobs you can get without IB experience. So why waste 2-3 years to go back to square zero? I am excluding the small part of MBA hires that are really talented and passionate about the job and know that they want to make MD's.