I've had two instant one-sided connections. Physical attraction was part of the first, stronger time. Both were in intense, kind of novel circumstances. Both people came across as trapped, misunderstood, and emotional. The first one clearly was headstrong; with the other, there were signs of that. The second person was downright weird. I never developed a real connection with person A. With person B, it took years for something possibly fleeting to happen, due to some degree of initial repulsion. Person B in fact is very stubborn, and my initial impressions of both proved correct. Just to make clear, I felt the way I did because I related strongly to them, and I immediately cared.
I think it would be interesting to turn this around and ask if any INFPs here have been the subject of "love at first sight" or instant connection and if so, was that looks-based?