Because a small bet is always looked up.
maybe, but I'm not sure if 100% of the pot is considered a small bet... and I doubt people are betting to try and get someone to fold an 8 anyways. They might make a big overbet (2/3*the pot) to get good value from someone with an 8 however
I guess what I am trying to say, is that if you check and they overbet the pot drastically, (all of this is in general, not each and every time...) they aren't doing it hoping you fold an eight, they are doing it hoping you have the eight (because they dont think someone will fold the eight) whereas if they just bet the pot, they are doing it with some mess like a busted str8 draw/flush draw/counterfeited pair, hoping to knock you off a similar hand/A high/pair that is scared of a double paired board. Its not like our hero's hand is face up and he is almost certain to have the eight.
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