Mastering Is Not Necessary

So often when people come the the end of a phase within their workout program, there is a fear about the set of workouts in the next phase? Will they be too hard? Can I keep up? Am I ready? Should I master the current workouts first? Should I repeat the this phase again?

These are all legitimate things to ask yourself and you know what? You need to more forward in the workouts. Mastering is not necessary.