Well by ‘bad’ do you mean they don’t have much playoff success? Or that their stats are bad? If their stats are bad and they are on a bad team, then that’s pretty convincing proof that player is not very good. However if they put up nice stats and are a star on a bad team, then that’s something else. Either they are just the best player on a bad team, or they are legit stars that need better pieces around them.
Like there’s players like Kevin Love or Demarcus Cousins or Kyrie Irving who put up nice stats but never made a playoffs being the main star on their team. That’s an example of players who cannot be primary stars but can potentially be nice supporting co-stars.
Then there’s players like Pau Gasol, Mitch Richmond, T-mac, Chris Bosh who put up nice stats, made the playoffs, but couldn’t get past the first round as the main star. These are guys who have hall of fame potential but are just not on very good teams. Put them on a good team and their careers become quite different.
Then there’s players like Clyde Drexler or Dwight Howard who are a tier above that who have good teams, can lead their team to the Finals as the main star but can’t really win once there.
Then obviously you have guys who put up nice stats and are on good teams like Magic and Bird and Kareem and these guys are obviously hall of famers.
So that would be the 4 tiers of stars I would say, here let’s use a group of PFs as an analogy:
Kevin Love tier – can’t lead team to playoffs as main star
Pau Gasol tier – can lead team to playoffs as main star but can’t go deep
KG tier – can lead team deep into playoffs or into Finals as main star but can’t win
Duncan tier – can lead team to a championship (and yes Duncan has done this with subpar teams like in 2003)