Why is a football made out of leather?
The soccer ball was made out of leather in the early years of
the game because leather is flexible and durable, and of all the
materials available at the time, it was the best choice. Leather
was used to cover the animal bladders that formed the air sack
inside the ball. Synthetic materials were experimented with as
chemistry developed, and eventually leather was discontinued as the
construction material of choice. The new synthetic materials were
flexible, durable and would permit a ball to retain its shape. Most
importantly, the new materials absorbed less water than leather,
and water adsorption was always a concern with the leather ball.
Just as an aside, today's soccer balls are all synthetic because of
the superbly uniform performance of the material and the ability to
resist moisture. Synthetic's overall performance has surpassed
leather's so it's better for ball construction.