Soreness is not any indication of working a muscle well, or of new growth to come. When you work the muscle on a regular basis (this doesn't mean every day, but at least once every 7 days), and you get used to doing high workloads, and you get sore less. Once you start taking a week or two, or more off, your body isn't used to it anymore.
What's with all these "make it sore and grow like a weed!" posts? Such bs.