There's always a reason why things don't work. I mean certainly, it could be an accident because accidents do happen (things that have a low probability of happening but, by definition, in a million of people they will still happen to a dozen and there's no reason one shouldn't be in that dozen, as low as the probability is), but sometimes there's just the lack of compatibility in terms of expectations, personality, hobbies, "chemistry" and the like.
It might be a good idea to try and look for the reason. Do we intimidate people? Do we have a persona that scares them (being "an original" in this or that way)? Do we have some habits or hobbies that alienate them? Do we somehow manage to convey the impression we're not interested in a relationship or don't care? Do we send apathetic or angsty or otherwise negative vibes? Do we give the impression we want a relationship so much it doesn't really matter who it is with? People don't like that.
The solution is not necessarily to change but rather to cast our figurative net in different waters, targetting a different kind of people, maybe making sure to explain certain things or prepare people for them. There's time for chitchat and there's time for talking about the meaning of life. ;) On the other hand, I doubt it matters that much when one meets the "right" person. Many people say when you meet the "right" person there's really little you can do wrong. I'm inclined to agree with them, although I have very little personal experience with that.
It doesn't hurt to put oneself in the other's shoes and talk and talk a lot about things. Misunderstandings often come from lack of sufficient communication and the biggest problem with communication is the assumption that it's taking place. Additionally, other people are as prone to mispresenting themselves as we are, so generally, it's always good to talk about things (not a brutal, frank way, but with some empathy).
Other than this, well, some people take long to find a match. I'm one of those people too, so I know. It's a matter of values, personality, hobbies, some combinations are difficult to match. One could obviously force a match to cut the waiting but that's what we call "settling" and it's generally not what we have in mind when we go out to meet people.
Where I'm driving at, also, is that the (apparent) inability to find anybody matching shouldn't give you the impression you're not attractive because of it (although it always helps to work on things that make us nicer to look at, talk to etc.), and you shouldn't lose confidence because of that. There are too many factors to it, with compatibility issues in the lead.
Anybody still awake? :p