Those who don't learn from their mistakes are doomed to repeat them.
That includes former UFC Interim Heavyweight Champion Shane Carwin, who punched himself into a state of suspended animation against then-division champion Brock Lesnar at UFC 116 last July.
The big man dominated the first round before his massive muscles could no longer get the oxygen needed to operate properly and gave way. He vowed to return stronger and better than ever, which he was initially set to do at UFC 125 against Roy Nelson.
However, "The Engineer" went under the knife to repair an ailing neck, which forced the promotion to insert "Big Country" into a match up against Frank Mir, instead.
A now-healthy Carwin was subsequently re-booked to welcome heavyweight submission specialist Jon Olav Einemo to the Octagon for the first time ever on the main card of the UFC 131 pay-per-view set for June 11 in Vancouver.
That is, until his manager informed him that event headliner Brock Lesnar had been submitted by diverticulitis (again) and they needed Carwin to take his place.
Will he redeem himself against Junior dos Santos and earn a crack at heavyweight champion Cain Velasquez? Or repeat himself and earn a crack at TBA on a future edition of Spike TV "Prelims?"
Here's what he tells MMA Fighting:
"First time it's ever happened to me in my life. It was terrible. I'm always in the zone in there. I don't see or hear the crowd at all. But I remember raining bombs down on (Lesnar) and then all of a sudden this whoosh came over my body, and then suddenly I could see people in the crowd. Like, individual people who I could see and hear. Then I felt my body slowing down. You live and you learn. If I get somebody in that situation again, I'll probably pick my shots better. I never disagreed with [referee] Josh [Rosenthal]'s decision not to stop it. Brock came back and beat me, so how can you argue with that? But it was all I'd ever known from my previous fights. That's how my fights ended, was me on top of the guy raining punches down."
Carwin feels that fighting Dos Santos to reclaim his title as number one division contender is "where he belongs." It likely won't be a walk in the park, considering "The Engineer" will be be making his return after nearly a year-long layoff following his arm-triangle loss to Lesnar.
"Cigano" cemented his place among the heavyweight big guns after a string of impressive performances against the likes of former Pride FC star Mirko "Cro Cop" Filipovic at UFC 103, Gilbert Yvel at UFC 108 and most recently against Roy "Big Country" Nelson at UFC 117 last August.
In fact, the Brazilian has enjoyed something of a UFC Cinderella story, being brought in for what was thought to be a squash match against Fabricio Werdum in his 2008 debut.
Dos Santos had other plans, knocking out "Vai Cavalo" and forcing the UFC to give him the best the division has to offer, mostly because he's destroyed everyone else worth mentioning in the 265-pound weight class, going undefeated (6-0) with five stoppages.
But can he withstand the powerful punches of Carwin? Will he have to? We'll find out in less than a month.
Who ya' got?