Yup, because somebody else might have even the same idea before. Also, idea's are generally speaking very cheap. In a world where progress is made in "smallis

Yup, because somebody else might have even the same idea before. Also, idea's are generally speaking very cheap. In a world where progress is made in "smallish" increments it doesn't make any sense to allow exclusive rights to the first one to apply for a patent. Furthermore, other industries that mainly idea-driven like fashion industry are less about protection, but more about advancing faster.