If you stop wanting to improve your skills you will cease to be good at your job. Don’t let short term success make you overly confident or complacent. While having a successful month, a good quarter or even a good year is great news it does not guarantee your success further down the line. All bets are on that a slump is out there waiting for you somewhere, and when it does, it can quickly turn things on their head. So you need to have a backup plan.