As a trainer, I often talk to people about the importance of consistency in their workouts. Little progress can be made if workouts are few and far between as the body has to get used to exercise all over again. Gains made are lost, and it can be quite discouraging to constantly feel as if you are starting again from square one. In order to stay motivated, it is important to feel as if progress is being made.
On the other side of the coin, equal importance must be placed on avoiding overtraining and the unavoidable occurrence of plateaus. Overtraining leads to the same kind of soreness, chance of injury and loss of motivation you get from lack of consistency. The old adage "no pain, no gain" should be relegated to the back of your storage locker along with those neon tops you wore in the 80's!