From this article about villains who c-bet too much:
https://www.pokernews.com/strategy/p...much-36333.htm

Hero (BB): 68
Button = Villain

Preflop:
Folds to villain who raises xxx, sb folds, hero calls

flop: A 7 9
hero checks, villain bets xxx, hero calls

Turn: 5
Hero bets xxx, villain calls


The article says:
"It also makes me think he didn't have a set or a good two-pair hand like A-7 or A-9 as he would have raised on this scary board."

Why should villain raise with a set or even 2 pair on the turn?

Raising 2 pair / sets is correct to deny equity of FDs or to get value from Ax hands.
Sure can be behind sometimes but long run raising turn makes money and especially
on a A795 board where only 1 straight gets there, if turn is T then both 68 and J8 get there so maybe more caution on the turn.

Hard for Hero to actually have specifically the 1 hand which makes a straight. Much easier for Hero to have draws. If you are just calling 2p and sets anytime any straight gets there, you are losing value. This is a "scary board" for 2p and sets not because of the slim chance of straights, which account for 16 combos, but for the 2 flush draws which account for a ton more (as many as 110? but you can discount many due to the action so far - point is its more than 16).

If you are playing against the entire range of Hero's hands, not the 16 which happen to have you beat, you are way ahead with 2p and sets. Raise for value, raise to cut the odds of the FDs and force Hero into a mistake if they call.

Because made straights are a tiny part of H range here. Bet/raise for value vs so many flush draws and pair+straight draws.

It's also highly unlikely that a donk lead by Hero is the correct play here.