This isn't something that ever really dawned on me before.....but I was looking on Wikipedia at a listing of the Saints's starting QBs going back to 1967, and unless I'm completely overlooking something....we only drafted ONE starting QB (Archie) who the consensus would agree was effective.
Bobby Hebert? Free agent from the USFL
John Fourcade? Free agent
Aaron Brooks? Traded to the Saints from Green Bay
Drew Brees? Greatest Free Agent ever.
Throw in other non-Saints drafted names such as Jim Everett, Heath Shuler, Kerry Collins, the Billy Joes, Jeff Blake.......and it appears to me that the Saints, as an organization, prefer to buy used models at QB.