May/June cover of USMS Swimmer

The reason that triathlon is popular and that swimming is not is that there is the notion that one can compete in a triathlon and not be very fast, and it is still ok. You will have a ton of other not very fast people to finish 20th out of 30 with you. And if you work hard at triathlon without any coaching (at least in the biking and running) you will get faster and beat more people. Many people find this rewarding. That's because it sucks to ALWAYS finish last no matter how hard you work. By contrast, swimming requires skill. Usually years and years of it. And coaching on a consistent basis helps a lot too. Picking it up as an adult is difficult and embarassing because you look like an idiot doing it and you know it. And you can work at it for years and still never be as good as someone who did it as a kid. The same cannot be said for biking or running. And speaking as someone who finished last in her age group in most of her events at her last meet (although to look at me swim, most assume that I swam in high school), I can tell you that it can be difficult to remind yourself that you are competing against people who have years of experience and coaching behind them (compared to your 1 or 2), and focus on the fact that you improved your time for your 100 free by 10 seconds. Most adults aren't going to want to do something with so little payoff.

The reason that triathlon is popular and that swimming is not is that there is the notion that one can compete in a triathlon and not be very fast, and it is still ok. You will have a ton of other not very fast people to finish 20th out of 30 with you. And if you work hard at triathlon without any coaching (at least in the biking and running) you will get faster and beat more people. Many people find this rewarding. That's because it sucks to ALWAYS finish last no matter how hard you work. By contrast, swimming requires skill. Usually years and years of it. And coaching on a consistent basis helps a lot too. Picking it up as an adult is difficult and embarassing because you look like an idiot doing it and you know it. And you can work at it for years and still never be as good as someone who did it as a kid. The same cannot be said for biking or running. And speaking as someone who finished last in her age group in most of her events at her last meet (although to look at me swim, most assume that I swam in high school), I can tell you that it can be difficult to remind yourself that you are competing against people who have years of experience and coaching behind them (compared to your 1 or 2), and focus on the fact that you improved your time for your 100 free by 10 seconds. Most adults aren't going to want to do something with so little payoff.