Why bet the pot?

[J.A.K.]

Where am I going wrong?

Blinds 10/20
Folds to MP1 who makes it 60
Folds to Hero (button) who calls JsTs 60
Blinds fold: Pot $150

Flop: Kh, 8s, 2s

MP1 bets $150
Hero calls $150
Pot $450.00

Turn: 3c

MP1 bets $450
Hero calls $450
Pot: $1350

River: Qs

MP1 checks
Hero Bets $500 MP1 folds.

Hero put in 60+150+450=$660 to win a pot of $1350= 2.05-1

Doesn't the flop potsized bet guarantee us our odds as long as the turn bet is pot or less? I am now committed to anything other than a crazy oversized turn bet. I know this is wrong but can't get my mind around it!! I know you adjust odds for 1 card to come, but there will always be better than 2-1 odds OVERALL with 2 potsized bets. My head is about to explode.