Not necessarily ..... not being over-attracted (or "desperate") is sth women tend to find as a signifcantly attractive quality. Is all about "being real" - to yourself and to her.
Real about who she really is - a (seriously-flawed) human, a person, a daughter, a sister, etc, etc - not just a "babe".
Since there's always a real chance of being rejected, why not prepare yourself for that possible scenario, by preventing yourself becoming overly/irrationally attracted?. And in doing that I suspect that ironically, you actually may become more attractive to them.
Real about who you really need in a life-partner. It might not be the case, but if you're only "into" the most attractive women, then i suspect you might be being "blinded" by their outwards beauty.
I don't mean to sound negative, but what if you aren't "good enough" for most of these women? (really beautiful women tend have notriously-high standards for certain aspects - such as looks, money, comforts). In her mind, she probably even rejects most guys who do have these things! (her top-priority things are satisfied, so she goes down the list, and maybe finds a lower-priority aspect (eg "things in common" or "can relate to") is not satisfied. Which brings me back to "being real" - whether two particilar people are "truly compatible" for each other (not "surface-compatible", as in most dating sites).