"In investing, what is comfortable is rarely profitable." - Robert Arnott
At times, you will have to step out of your coziness to realize significant gains. Know the boundaries of your luxury and practice stepping out of it in trivial hit. As much as you need to know the market, you need to know yourself too. Can you handle staying in when everyone else is jumping ship? Or getting out during the biggest rally of the century? There's no room for pride in this kind of self-analysis. The best investment strategy can turn into the worst if you don't have the stomach to see it through.