My one regret was that my Mum who was a championship level swimmer in her youth never taught me to swim. Or took me swimming. OK I had lessons at Secondary school (once a week, Summer term) and just about managed a breadth of the pool, but to this day I am scared of water, would never go into a pool for pleasure, am petrified of being out of my depth and basically avoid it at all costs
I even tried adult swimming lessons at my gym a few years ago which went well for about 4 weeks then our teacher said he was taking us to bigger and deeper pool to learn how to tread water and I just didn't go back.