A city also has abundance and access, especially for the young, but as people pair off, and as they corral themselves, through profession, geography, and taste, into cliques and castes, the range of available mates shrinks.
Some add an extra layer of projection and interpretation; they adhere to a certain theory of compatibility, rooted in psychology or brain chemistry or genetic coding, or they define themselves by other, more readily obvious indicators of similitude, such as race, religion, sexual predilection, sense of humor, or musical taste.
Or you see someone until someone better comes along.
The term for this is “trading up.” It can lead you to think that your opportunities are virtually infinite, and therefore to question what you have. For some, of course, there is no end game; Internet dating can be sport, an end in itself.
You fall prey to the tyranny of choice—the idea that people, when faced with too many options, find it harder to make a selection.
If you are trying to choose a boyfriend out of a herd of thousands, you may choose none of them.