For untold centuries old timers have been bending natural materials.
Some materials bend more easily than others.
We have always been looking for ways to improve the bending of natural materials. When we bend materials, there are two stresses. Obviously, the thinner the material is, the easier it is to bend as the inside is compressed less and the outside stretched less. Old timers spent much time looking for the choice piece of wood that would not break when it was bent. Steaming When wood is dry it isn't very flexible.