Years after the Civil War, my grandparents opened a bar next to the Sanctuary of Guadalupe in Hondarribia. It was the second business they ran; the other was in Irun, just five kilometers from the sanctuary.

That bar would fill with thirsty worshippers after Sunday Mass and shepherds who, in their daily routine, guided their livestock through the nearby meadows. But there was a special time of the year: during the nine days leading up to the patron saint festivities in honor of the Virgin of Guadalupe, the donut seller would arrive with his goods. His customers were the same parishioners who later stopped at my grandparents’ bar for a glass of sweet wine, the famous ardo goxo in Basque.

My father used to tell me that this donut seller was known not only for his donuts but also for his austere life, bordering on destitution. Yet, no one could compete with him on price—his donuts were the cheapest in the area.

One day, when he was young, my father dared to ask him how he managed to sell them so cheaply. The answer was revealing:

—Young man, there’s no secret here: I lose one peseta on every pack of donuts.

—But then… you’re losing money! —my father replied, surprised.

The donut seller, smiling, answered:

—No, because I sell a lot!

Coach, this lesson is for you.

Make sure the net value of each of your training sessions is positive. Otherwise, you’ll become the donut seller of Canoe Slalom: the more unprofitable training sessions you accumulate, the worse it will be for your athletes.

Keep your concepts up to date. Ensure your methodologies combine science and experience. Don’t confuse volume with value. Because if each session costs more than it contributes, selling many won’t make the numbers work in your favor.