Whoever taught you to swim gave you something you’ll use for the rest of your life. Some gifts don’t fit in boxes.

Some things given to you cannot be returned, resold or used up. Being able to swim sits in your body for life, gets used on holidays you have not had yet, and may one day matter enormously, and whoever gave it to you spent a few afternoons on it and thought nothing of them. The size of the gift and the effort behind it do not match. That is true of most of the important ones.

Worth working out which of yours arrived that way, and from whom. Then notice that you are now able to hand somebody something of that size, cheaply, on an ordinary afternoon.