The difference is Joe Quesada was actually competent and actually was able to get good creative teams on books for long runs. Not withstanding crap like Sins Past and OMD, together with Jemas he launched the Ultimates line with Millar and Bendis and for the normal stuff you had Bendis writing DD, Brubaker on Captain America, JMS on Thor, Fraction on Iron Man, Pak on Hulk, Slott on Spider-Man, the revitalization of the cosmic Marvel side of things and GotG (that spawned the movie) with DnA as well as stuff like Civil War. In contrast for Didio at DC there was just never a prioritization at maintaining creators on books for long runs (except for Johns on Lantern and Morrison on Batman and both of these were the work of Pete Tomasi). If you look at the statistics of the One Year Later soft-reboot that happened post-Infinite Crisis, the majority of creators were gone within two years. You see the same pattern on Nu52. There was a recent interview with Devin Grayson and she pretty much said that he pretty much hated the idea of Nightwing (as well as the Earth Angel Supergirl), management made writing the book incredibly difficult constantly requesting changes to scripts (which mirrors the interview Fialkov gave to Bleedingcool about Nu52) and that she was never even told about what he was planning to do (the destruction of Bludhavn and the death of Nightwing). I think it really shows the problem with his style of management at DC basically taking these unilateral actions (ordering Nightwing to be killed or Barry to be brought back and DC Universe to be rebooted), without consulting anyone (including the writer for these characters and their books) and why you have this constant revolving door of creators on books with few of them staying more than two years.