I'm sure that I misplayed this, but I'd like to know how specifically

Blinds 500/1000/100
My chip stack: ~50,000
Button's chip stack: ~ 22,000

I'm in the small blind and it's folded around to the button who raises to 3000. I've seen him raise all in before now preflop with J9o and other such hands when it's limped to him in a multiway pot and he's the big blind.

I have KK in the small blind and flat, big blind folds

The reason I flat is because I think it's a button steal and a raise will scare him off and I want a bit more value

Flop comes A23 rainbow

I check
Button checks

Turn comes 5

I check
Button checks

River comes 9 (no flush possible)

I value bet 6000
Button raises all in

I call the 13,000 extra and he turns over 910o

Sure I win the pot, but what should I have done being non results orientated?

Dont think i bet that river for value. Not much hands will call tou with worse

I say you have to raise preflop. He has only 22,000 and bets 3,000. Go ahead and shove it. Maybe he will fold. Then you gain some chips and don't have to play a hand out of position. Or maybe he'll call you with a much worse hand and you will be a big favorite to knock him out.

The worst thing you can do is play a raised pot out of position. If you check and he shoves the Ace high flop, are you going to call? That is a very difficult decision. As it was, I'm sure you weren't happy calling on the river - though it turned out fine.

When you get to the late stages of tournaments, never be afraid of making someone fold. Every chip you get uncontested is a chip you take away from someone else.

I'm pretty sure you know where you misplayed the hand.

I've noticed that sometimes...players like to get to much value from hands and it ends up backfiring in critical spots. This could have been one of them.