Someone posted this in another thread, but I feel it's worthy of it's own discussion. Sam Quinn's rankings and tiers were:
Tier 1: The undisputed king
1. Erik Spolestra
Tier 2: The elites
2. Nick Nurse
3. Rick Carlisle
4. Steve Kerr
5. Ty Lue
Tier 3: The Wunderkinds
6. Mark Daigneault
7. Will Hardy
Tier 4: Obvious floor-raisers
8. Ime Udoka
9. Mike Budenholzer
10. Tom Thibodeau
11. Joe Mazzula
12. Chris Finch
13. Mike Brown
Tier 5: The living legend
14. Gregg Popovich
Tier 6: Middle of the road
15. Mike Malone
16. Quin Snyder
17. Taylor Jenkins
18. Jason Kidd
Tier 7: You look promising, but it's still a tad early
19. Jamahl Mosley
20. Willie Green
21. Kenny Atkinson
Tier 8: I wouldn't be enthused
22. Doc Rivers
23. JB Bickerstaff
24. Billy Donovan
25. Chauncey Billups
Tier 9: We don't know enough
26. Darko Rajakovic
27. Jordi Frenandez
28. Charles Lee
29. Brian Keefe
30. JJ Redick
He also provided his criteria, which is always appreciated in something this difficult to evaluate:
- Track record. This is obvious. A great coach tends to win a lot of games in the regular season and advance deep into the postseason.
- Performance against expectations. Sometimes, a great coach is stricken with a limited roster. Can he make lemonade out of those lemons? Some coaches happen to consistently find themselves with elite talent. What does it say about them if they can't make the most of it?
- Points of emphasis. Do your teams take the right kinds of shots? Do they allow the right kinds of shots? Do you have ways of generating turnovers without excessive fouling? Do you balance rebounding and transition on both ends of the floor? Essentially, is your team doing the right things on paper? Are you plucking the low-hanging fruit?
- Creativity. Have you found unorthodox uses for under-valued players? Are there things that you do that other coaches don't? Can you draw up a nice out-of-bounds play?
- Player development. Do your draft picks pan out? Do you find productive players on the margins? Do players leave your team and get better? Do players leave your team and get worse?
- Rotation management. Are you playing the right players? Are you overusing your best players? Are you underusing them? Do you have specific lineup quirks that help or hurt your team consistently?
- People management. Do your players like you? Do they play hard for you? Are you operating in lockstep with your GM? Are you constantly battling with ownership? Can you manage the politics of your locker room?