I am single right now for many different reasons.
1 The vast majority of women that I would be attracted to would not be attracted to me. And I could lie and say that I am attracted to women that I am not attracted to, because actually the most important thing for me is to find someone with points 3 and 4 but I don't think that is right and I think that would be dangerous for a relationship (in my case I would be looking for marriage) because most women need to feel like they are attractive to their husband
2 Hence it would take to long to find them
3 Even if I did spend all that time I would need to have someone that didn't demand too much attention and didn't make me feel that my life was out of my control
4 Even if they didn't demand too much attention I would need them to have similar interests and moral beliefs so I wouldn't feel like my marriage was detracting from what I feel is my main purpose in life
5 Even if all that is met I would still need to figure out if it would work because I still think marriage might distract me from my goals more than it helps me (I may really just work better alone)
6 Making sure 3-5 are met would take even more time
7 I may be too lazy to figure all this out anyway
8 I spend the time I save by not searching for love by writing about it on message forums, so there goes all the time I would have free to do all this (well im only joking about that, I just joined so I can't say that yet)
But all these reason may be because I've built up a set of pseudo-rational road blocks to protect my ego and prevent more embarrassing social failings on my part in the future. As I have the ability to reason through my social interactions correctly only after the fact and am usually horribly embarrassed once I realize what I have done, it is very painful sometimes.