I can safely say that the largest factor for me when it comes to dating (and women in general) is receptivity.
But before I explain and qualify myself, permit me to paint a picture that clearly shows the difference between an encounter with someone who is receptive and someone who isn't. Let's say I'm in a room full of singles ready to mingle. I am taking my time walking around slowly, allowing myself to scan and note anyone I find potentially appealing or attractive. That's how the first impression works, and I've come to trust in what I find interesting.
And let's say I see two women that I am interested in talking to, and perhaps for the sake of this illustration I will posit that I find one significantly more attractive than the other at the moment. So, as I mingle and make my way around the room (assuming I wouldn't just make a beeline for whomever I found interesting), I look over a few times. Say the more attractive one is oblivious to my existence, and the other attractive woman looks back and smiles. Can you guess which I would approach?
I would not give it a second thought. If there were a balance and the initial attraction had it tipped to one side, at this point it would be almost entirely weighed on the other side.
What I'm hoping for is an indication of potential interest because -let's face it -I know how I feel and what I am thinking, but not what she's thinking or feeling. I'm just not very likely to spend or waste my time trying to charm or convince a woman to be interested in me. Furthermore, with every response, smile, laugh and look I will find myself more attracted and interested in this woman and less interested in the other one.
In one sense, it's not super complicated: we are more attracted to people who we think and feel are attracted to us. That's why hearing a woman likes me or has an interest in me will more likely pique my interest in her.
The same has been my experience with online and shidduch dating. Whether it's because of emotional (interest/attraction) or logistical (school/work/being busy) factors, I'm MUCH more into a woman who is available and responsive to me (and of course we have lives, I don't expect 24/6 responsiveness).
And there you have a definition for receptivity: being available and responsive. Body language and nonverbals are just as important as listening and being open to hearing and responding to whatever stories, thoughts or jokes I'm sharing (and of course that goes two ways as well). It's not just about responding, but how she responds too.
Receptivity is honestly, seriously, actually, very attractive. Downright hott. It easily tips the scales for me.
I naturally gravitate towards people who are more responsive to me, and I assume that's the case for most people. On the flip side, when I sense less receptivity, I'm often finding myself less interested, less invested and less attracted.
Some people think that "playing the game" -when they wait, hold back and are not very receptive -works better. Maybe in America we were raised and told to play our cards close to our chest, to give up as little as possible it's understandable that people would do so. I would much rather smile and see smiles, tease and be teased, to quip and use wordplay, push away and pull in with playful communication.