In the world of baking, cookies are among the easiest things to make. You don't have to be accomplished in the kitchen to bake a wonderful batch. No special skills are required. All you need are good ingredients, a few basic tools, and a little know-how. It also helps to have the weather on your side.
Cookies are little sponges-they absorb moisture from the atmosphere.
On a hot, humid day they can turn from crispy-crunchy to soft and limp within hours. Inconsistency is the bane of a baker's reputation. They know their dough. If it needs less liquid on a given day, they hold back. My great aunts never measured.