Why do guys look girls up and down?

Those dudes want you to know they are idiots! Not that the person is pretty or hot ( I'm sure the person is) but that they can't even sensibly find interest in a deep level and embarrassingly so by objectifying beauty instead of admiring what makes the so..:p lol
Mostly, check out the figure, it's like a manual scan of masculinity.
You will notice mostly men do that and it's not weird.
Doesn't mean a wrong intention to it.
Just a nature of guy when they sight a girl.
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Seems pretty simple to me. You don't know each other. First thing you do is decide if the other person is attractive to you visually. Men are genetically designed to do this. In nature, the males will mate with as many females as possible. This action begins the selection process. Now it's up to the women to send back signals to the man that she is interested. Often the man fails to recognize these signals and nothing happens.
The women walks away dejected and hates men for the rest of her life.
To be more serious. I think many men fail at this. It often comes off as crude and insensitive. Men don't often like to feel vulnerable around other men. Women are usually more attracted to men who show that they are vulnerable. It's really just a bad situation and you need to look more closely at who is looking. Look for the quite one.
He is the one you want.
Simply to determine if they are attracted to the girl... some guys will be blatant about it regardless of where they are or who they are with other more restrained if working or with their partner, family, other friend who is a girl... they will do it far more subtly... just wonder how many car crashes have happened because of that!
Well, guys like that are what I like to call, "Creeps". No respectable dude just scans a girl right in front of them.
For that very reason, they don't care. They are openly checking you out. If you like them back you will say something. That's how relationships are made sometimes
Many guys don't care about getting spotted checking you out; they just wanna check you out.
its called checking them out, you gotta check the whole package
Some have the misguided perception that it makes them look good.
For the same reason girls dress for sexual attention... girls want the attention and guys give them the attention.
Because they don't care that you see them
They’re making sure they have no bugs on them
Because they don't?
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