Ah, coolers. One of the most dreaded things in poker. The event that just pisses everybody off when they experience it.
For those of you who don’t know what a cooler is, it’s basically a situation where a strong hand gets beat by an even stronger hand. It’s a practically unavoidable situation, because folding would require putting your opponent on a hand that is extremely unlikely for them to have.
When these happen, of course they frustrate me a lot. However, at the same time, I am much happier to lose money to a cooler versus a time where I just played poorly. Often times, you can’t really do much about a cooler. When you’re only losing to quads or a better full house, it’s very hard to lay your hand down.
The silver lining is that there will be times where you’re on the winning side of a cooler, which over time evens out for the most part.
Here is an example of what I would say is the ultimate cooler, from the 2008 WSOP main event:

You’re never folding quads though. I’ve never lost with quads and I would never fold quads. I bet it’ll happen eventually if I play enough online hands. However I imagine it would take me at least 100,000 hands if not more for that to happen. Folding a boat is hard enough, folding quads is pretty much impossible.
Some people have made pretty impressive folds to avoid a cooler.
There are some scenarios where folding a boat does seem possible, however they are few and far between.
This is, in my opinion, the most impressive fold in the history of poker:

Putting Ruane on JJ or QQ would be quite difficult given the preflop action. I’m not sure if Obst was actually putting Ruane on a straight flush. It’s possible that Obst put him on a hand like QT or JT, but that would still be a very difficult laydown to make.
That being said, this is an extremely impressive laydown. Possibly the best I’ve ever seen in poker. 99.9% of players would not be able to fold here. Myself included.
Recently, I experienced a pretty brutal cooler. I rivered the nut flush and lost to flopped quads. This happened in a private 2c/5c home game so I don’t have the full hand data.
Part of me thought that my opponents may have had a boat. Quads or a straight flush was way too hard to put them on. You really can’t put your opponents on either of those hands, as they’re so rare to begin with.
Here’s another hand I played recently:

Flopping a set on that board was bad enough. AJo isn’t that good of a hand, so calling a 3x raise is pretty reasonable, especially out of position.
I bet big on the flop, about a pot sized bet. Flopping a set on a triple suited board leaves it very vulnerable. I wasn’t going to let them make a flush or straight without paying for it. On a 4 to a flush or straight board, the set would be quite vulnerable.
At this point, I was putting my opponent on one diamond, maybe a pair.
The turn being an ace made me feel quite comfortable. I now had a boat so I wasn’t losing to a straight or flush anymore. However, this ended up being the card that costed me a good portion of my stack.
The river was a blank. Ultimately the money was going in here. At that point I was putting my opponent on a flush or maybe trips. Putting them on a boat was next to impossible here.
I suppose putting my opponent on AJ wasn’t impossible here, but it would be an incredibly difficult laydown to make.
Bottom line: Coolers are mostly unavoidable. They suck, but eventually they even out in the end for the most part.