What really turns me off is when I see someone who assumes immediate compatibility merely because of their own initial desire for their target. This happened to me all the time during the brief interlude I had with internet dating (don't get me started on that). I would receive messages in my okcupid inbox that literally read, "FINALLY!" or, I kid you not, "I think we'd be really compatible because I find you mind-numbingly attractive." For real -- that's the causation right there? We're compatible because YOU find ME mind-numbingly attractive? What about me and what I want? Is our compatibility affected by whether I find you attractive, or do I just not get a say in the matter?
When we foist our desires upon our target too soon, we are essentially telling them that they don't get a say in the matter. We want a relationship, or a house and kids, or whatever it is that we want, and because we are ready for this at this point in our lives, they ought to deliver, and their own needs don't really count.