Usually longevity is among the most important factors for a fighter to be defined as an all time great. Who, by your definition, are the ATGs who did LEAST? What about regular greats? Which definitely great fighter did the least? If Rigondeaux counts as a great (probably not), he might be suitable for this second group
Among guys considered ATGs, it's gotta be Bowe. Peaked in the early 90s, washed up by the mid-90s. But really I say Bowe because many of us say he only peaked in one fight. Generally, to reach the level of ATG, you gotta have at least a 2-3 year prime. I'm thinking Tyson, Pryor, Curry here. All had about a 3-year prime. Matthew Saad only had 2-year prime. Mike Nunn I would argue was a great fighter in his very brief prime, which essentially only lasted 2 years. But no one really considers Nunn an ATG. He's a guy who could have been an ATG.
I do think Rigo counts as a great, BTW. I think he deserves to be in the HOF. But there's levels of great, at least IMO. He's not an ALL TIME GREAT, but he had ATG level talent.
Then if Bowe doesn't meet your ATG criteria, I would say Saad, who's a consensus ATG. Saad's prime was shorter than Tyson's and Pryor's.
Tyson might not even belong here, because Mike never really fell off a cliff like Saad, Pryor, and Curry did. Tyson was past his prime by the early 90s, but he was still a quality fighter (compared to the division) up until 2000. Pryor and Saad were journeymen level fighters by the mid-80s. We know that of Pryor because he got knocked out by a journeyman.
Are we just talking about great fighters whose prime didn't last too long? If so then I would say that Salvador Sanchez's prime was pretty short lived. He was at his best when he beat Danny Lopez in 1980 and he passed away 2 years later.
Fighters who can be considered great who did the smallest amount of work. Usually it is guys who had special level of talent but for some reason we only saw it for a little while. Thus, Sanchez is an excellent nominee
He did, but he has an exceptional amount of classic fights. Plus, Hagler win is arguably his greatest achievement. Sanchez' prime was short and he had few truly classic fights, yet he is clearly an ATG. Thus he is the leading candidate so far
Carlos Zarate, prime only lasted 76-78. Though to be fair, he was in his prime before he won the title from Martinez.
Even though he's not in the IBHOF (which he should be) Lionel Rose deserves a mention for short primes. His prime started around 1967 when he fought Rocky Gattelari and Fighting Harada and it ended by the time Olivares stopped him in 1969.
Happy Lora is in the exact same boat as Rose. Very brief prime, but got a lot done in that short span. Rose and Lora should both be in the Hall. They're arguably the two smoothest boxing bantamweights OAT.
You can add Gilberto Roman as well, another smooth boxing master that should also be in the IBHOF but also had a short prime from 1986 to 1989.
