Readiness is a quality of being able or willing to do something. An athlete's readiness for the Olympics has to do with how warmed up she is, whether she's recovered from injuries, as well as her psychological state.
Your readiness for something usually has to do with how well prepared you are. Your parents might have decorated a room and bought a crib before you were born, in readiness for your arrival. And local police sometimes clear the streets and direct traffic away in readiness for a big parade. Readiness can also mean "willingness," like an eager kindergartner's readiness to learn how to read.