1st round - needs to be a productive, reliable starter within a season or two while showing something as a rookie. the "starter" designation is less important if it's a position that gets rotated heavily or if it's a quarterback drafted to sit behind an established veteran. in that case they just need to be productive when given snaps if they get the opportunity. if a player from this round busts it hurts the worst.
2nd round - needs to eventually become a starter or fit into a rotation. it would be disappointing if they don't show anything (think dwayne jarrett) as a rookie. busts still hurt but the expectations are lower and the value of the pick is smaller the further away from the last pick of the first it is. spending what turned into the 33rd pick in 2011 to get armanti edwards in 2010, for example, was a major blunder as that's about as valuable as a second round pick can be. development time for DL and OL positions needs to be considered here as the prospects that fall to this point in the draft may not be as polished as their first round counterparts. also need to look at position groups and consider whether it's reasonable for a non-first round rookie to challenge established veterans for snaps.
3rd round - needs to at least fit into a rotation or contribute on special teams at some point. it's less disappointing but still slightly worrisome if they don't show any flashes as a rookie or second year player. at this point it's to be expected that a rookie from this round would have trouble breaking into a stacked position group.
4th round - 6th round - players selected in these rounds don't earn the "bust" label if they fail to become starters or contributors. expectations for prospects drafted in these rounds are depth/special teams. if a player from this round turns into a good rotational player then it's a good pick. if they turn into a starter or all pro/pro bowler then it's a great pick.
7th round - UDFA - i'm not disappointed by these picks not making the final roster. if they challenge for playing time then they've exceeded expectations. if they become productive starters then that's outstanding.
And yes, you can find an OL who was drafted after Kugbila who has had more success. I bet for every one you find drafted after Kugbila that succeeded, I can find one who was drafted before Kugbila and failed. One case does not prove a point.
like most 4th rounds it consisted of one or two solid players with name recognition surrounded by a bunch of guys nobody has ever heard of:
the panthers maybe haven't done a lot to drop as many wide receivers around cam as possible but you're just being a hard headed idealogue if you look at a 1000 yard first round rookie receiver and make up a bunch of excuses for why it doesn't count
edit: the pro bowl tight end on this team seemingly doesn't come up in these discussions much either
just a heads up but this site is going to hate you when you don't double dip at wideout in the first two rounds. also i know you don't give a hot poo what a bunch of armchair GMs who don't have to write million-plus dollar checks think but this is more of a rhetorical exercise and whatnot