I will occasionally look when I pass a cute guy on the street, but I almost immediately chastise myself for it. Like PopBoy, I have self-esteem issues, so the conversation with myself will go something like this: "Ooh, he's cute -- no, stop looking. He'd never be interested in you. Why bother?"
What got to me about both of these was this -- why, if they were interested, didn't they just say "hello"? So I figure they weren't so much interested, as being creepy. (There's that low self-esteem thing again, I guess.)
They might be suffering from the same self-esteem issues.
"She's attractive, She'd never be interested in me, Why bother?"
Men can suffer from low self-esteem/self-confidence etc.. and remember whilst it shouldn't be the case more often or not they are expected to make the first move, the first to express an interest.
And of course on the occasion that you do manage to overcome those issues and say hello, express an interest and get rejected it makes you more weary next time of doing it. It can become a visicous a cricle.
And yes it's easy to say, nothing ventured, nothing gained; you've got nothing to lose by trying etc..
I think you've got hold of the wrong end of the stick there (if I may use that idiom in this context). I'm well aware that some men have low self-esteem... I am one.

(Don't worry, I'm not offended... just amused.)
I actually had an experience a few years ago, on Pride weekend, where a straight guy from Calgary who happened to be in the bar with friends took it upon himself to try to get me over my shyness by teaching me how to pick up a guy. As I recall, the main point to his lesson was this: if they say "no," what's the worst that will happen - what are the odds I'll ever see the guy again?
It worked for a while, but I've kind of lost the knack. It doesn't help that I just turned 45, and most of the guys around my age are either happily coupled or have given up.
Mind you, that only works in a bar environment, where the chances of more than a one-night-stand are low. And while I've enjoyed a few of those in my life, it's not really what I'm looking for.
I can think of a couple of guys I've known over the years whom I kind of regret not having expressed interest. Of course, they're both in happy relationships now...
i work for a music management company that look after a-lists to z-lists. its mundane actually. Today i had a 50 minute fone call from an x factor entrant calling (and moaning) as to why management hadnt called her. maybe because shes bonkers. Anyway.
a very famous singer from a boyband came into the offices today. straight. i had to do some data entry (thats my job basically - the agency is glamourous. my job is not). and when he wasn't looking i 'caught myself looking' but not at his face but at his crotch.
HIS CROTCH!
He then saw this and walked away. He then said something to his friends and yes they laughed at me.
This is why i do not do public well.
If I may ask ... Who was it? Which boy band? I'd probably get conscious, too, if someone was checking out my crotch. But sometimes you just do things
unconsciously.
I was going to ask, was it Niall, Liam, Harry, Zayn or Louis?

(Not that I'd blame you. And if it was one of them, they do kind of play up the ambiguity on stage...)