You should always be working on constant improvement.
In order to attain personal and career levels you must always find time dedicated to improving your craft. We have an unlimited supply of books, blogs, video, audio files, in person and online classes (Thank You Internet). There is not a single reason you could give me as to why you are not always trying to learn sometime new or improve what you know. You don't become an expert overnight in anything. It takes a day-by-day, hour-by-hour process of focusing your mind on knowing what you didn't know yesterday.
Dedicate yourself to mastering your craft. Being anything less than the best at what you do is a waste if your valuable time.