The COLA(Carry-Over Lottery Allocation) system is the best system I’ve seen proposed to solve tanking.
Basically, the system explained simply as I can is:
Everyone who misses the playoffs gets the same amount of tickets. Once you’re eliminated, losing extra games gives you nothing extra. So there’s no reason to tank after you’re clearly out.
Tickets roll over (“carry over”) If you don’t win a top pick this year, you keep your tickets and add more next year. So a team that’s been bad for years slowly builds a huge pile of tickets and eventually becomes very likely to win.
Winning resets or reduces your tickets To keep it fair: If you win the #1 pick, your tickets reset to 0. If you win #2/#3/#4, your ticket stash gets cut down by a big percentage. If you do well in the playoffs, your ticket stash also gets reduced (because you’re clearly not weak).
So COLA rewards teams that are: bad for a long time, and/or unlucky in past lotteries
Why this reduces tanking: Before you’re eliminated, you still want to win to make the playoffs. After you’re eliminated, you can’t improve your odds by losing more. So tanking doesn’t help teams.
Here’s the full proposal: https://arxiv.org/html/2602.02487v1