If a man finds a woman physically attractive then he has a pre disposition to want to be with her, to perhaps chat her up, flirt, be close to her... etc etc etc.. Show indications of emotional interest.
(Not counting guys already in relationships)

Therefore since we are all human it stands to reason that if a woman finds a man physically attractive she will do the same... Is that reasonable ? If she does not do that, then she simply does not find him physically attractive. Is that reasonable ?

Yes, but her definition of "physically attractive" may not be the same as his definition.

What about her attracts him? What about him attracts her?

I believe there is a thread somewhere on this site about male vs. female attraction.

I may also add to Wondergirl's answer that thinking someone is physically attractive does not mean you want to be with them.
There are men I find attractive but I have no desire to be with them. There are other things I see or situations that are in place that takes away from what I see.

I believe that you can find a person attractive, but still find something about them that you wouldn't be attracted to them for. There's a classic example of a guy or girl being very attractive, but they're really ugly on the inside.
I don't know about everyone else, but the way I see a person changes as I get to know them. My best friend in the whole world is 300 lbs. When I first met her, that's all I saw. But when we started talking and relating to each other, she now appears to be one of the most beautiful people I know.
On the other hand I started talking to a guy I thought was attractive at first, but he had some weird things about him that made me find him quite gross later..
In short, I believe, instead of saying you are attracted to the people you find attractive, I would say you are attracted to the person that you cannot find anything unattractive about.

Ok...

To answer your questions, not necessarily. I have found many men to be quite attractive, but I only saw as friends, not as potential lovers.

Also, if a woman doesn't confront a man, doesn't mean that they don't want to have a potential relationship. There could be many reasons a woman doesn't. She could be shy, or afraid that SHE will get rejected.

Crazy, I know. Us women, quite an enigma. ;)