Do implied odds go down each round?

I have never heard this concept before and I wanted to make sure my logic isn't faulty.
This question is kind of directed towards no limit hold'em but I think it applies to all forms of poker.

In general are your implied odds on the flop (or earlier street in other forms of poker), better than the implied odds on the turn? Let's say you have a straight draw and you make your straight on the turn. You now have two turns of betting to build the pot whereas you would have one turn of betting if you made your straight on the river. So I would logically think you could call a little bit bigger bet on the flop because of the little bit larger implied odds then you could on the turn.

Did I miss something here?

[RoundTower]

This is correct. You could argue it is more important in limit hold'em because the missed turn bets are gone forever, whereas in no limit you may only need one street to get someone's tank.

[Xhad]

There is at least one exception: Sometimes, a good player will call bets on the river that they wouldn't call on the turn because they think you might be bluffing and want to see a showdown. The rationale is that it's worth one bet to find out you're bluffing, but not two.

Other than that, you're probably right.

[AaronBrown]

Aside from Xhad's excellent point, I would restate your thesis as implied odds approach pot odds on later rounds.

You're thinking of a situation in which your implied odds are greater than your pot odds, in which case the implied odds go down. But there are also cases in which implied odds are lower than pot odds, in that case the implied odds go up.

The player who gains the most information from undealt cards will have better implied odds than pot odds. The player who gains the least information will have worse implied odds. Generally speaking, drawing hands get more information from undealt cards, made hands get less.