It makes it too easy to find people, to ditch people, and most importantly, to date people who are similar to us.
Dan Slater asks whether online dating leads us to value our relationships less and whether that is a problem. I agree that it's a problem, but it isn't the only problem. Or rather, it's just a small part of a bigger problem with online dating. And the problem isn't really just a problem with online dating—it's a problem that extrudes from online markets in general: They lack sufficient friction, and paradoxically this is not a good thing.
A frictionless market is one that puts together buyer and seller without transaction costs. In the real world there is no such thing as a frictionless market, but some markets have more friction than others. Online markets reduce friction drastically in that they make the shopping part laughably easy.
Let me illustrate this point with an example that has nothing to do with dating. It is a deep dark secret of mine that I used to be a philatelist—yes, you can denigrate that fine hobby by calling it stamp collecting if you wish. I collected certain kinds of 19th-century postal history (mailed envelopes) and I used to enjoy travelling from dealer to dealer digging through bins of musty postal history looking for the items that I collected. And then the Internet happened.
Collecting postal history has gone from a labor of seeking out interesting shops and sales and digging through musty boxes to one of logging on to eBay, typing in a search request (19th-century postal history), and clicking on whatever envelope covers catch my eye. The search process has for all practical purposes become frictionless, and the net result is that it just isn't fun anymore. My collection has been placed in a storage locker. I'm done with it.
Now I realize that the economic language of frictionless markets isn't very romantic, but the fact is that the dating game is a kind of market whether we want to admit it or not. Finding a partner used to be expensive, and the market was inefficient. If you lived in a large city, there were always people looking for partners, but the problem was how to find them. Pick-up bars were imperfect markets to say the very least. Now you go online, select a partner, and you are immediately dating someone who is at least interested in you. Of course online dating is still work, but the emotional labor and risk of failure has been significantly reduced.
Slater picks up on two unintended consequences of a low-friction dating market. First, if it is too easy to find something you just don't value it as much. If diamonds grew on dandelions no one would care about diamonds. The other consequence is that it reduces the cost of moving on to something new. Not only is what you have less valuable, but trading for something new is less expensive as well. Sure, there is the breakup drama, but online dating markets mean you won't have to suffer that drama sitting home watching sad movies; you can find a replacement within days.
I agree that those are two of the problems with online dating markets, but they are really just the tip of the iceberg. Here is another problem that I consider to be more serious. One advantage of inefficient dating markets is that in times of scarcity we sometimes take chances on things we wouldn't otherwise try. In times of plenty, we take the path of least resistence (someone who appears compatible) and we forgo difficult and prima facie implausible pairings. And this is our loss. 1950s romantic comedies turned unlikely pairings into a formula—happenstance throws two unlikely people togetherand the sparks and romance begin. We all understand this kind of romance—it involves the strange chemistry of putting together two people who are, on the face of it, incompatible. Of course online dating services can randomize their matching algorithms to supply unlikely options—but these options are always served against a backdrop in which more likely options are plentiful, easy to obtain, and on the face of it less risky. We need the scarcity to propel us to try the unlikely pairings.