It depends on what you consider a weak draft. So often people say this draft is weak, because it lacks a LeBron type talent in it. Hence why 14 is so hyped up due to Wiggins, etc.
Irving was considered a weak prospect going into the draft. Sure, they thought he was super talented, etc, but rarely was he getting called a game changer/franchise player type talent. Maybe a future all star. Right now he's looking like one of, if not the top PG's in the league and he's only what? 20?
Lilliard was going to be good, but this good so early?
It just all depends on where the guys lands, his position if it's filled already or not (meaning if he's thrust into playing time, has to carry the load, etc.). Who's coaching him up. All sorts of factors.
Leonard, Faried, all these guys are not big time impact players, and they weren't considered this going into the draft.
Of course you're still going to have your busts and whatnot, but with the right scouting you can hit big anywhere in the draft, despite how weak or strong it can be labeled.