Sometimes if you are doing really well and have a good streak going, I like to move up in stakes even if you have not really crossed into your next bankroll "zone" yet. And likewise for losing streaks, that you might want to move down a level instead of having the midset that you need to get your lost money back. Moving down will help you get your game back because you will more likely play to win as the money is not that big of a deal at that stake level.