Sales slow. When you don't have sales coming in, you will not be able to cover personal and business expenses. To remedy this would be to get into action. Maybe you were taking action before, and this might require taking BIG action. "Don't mistake movement for achievement." - Jim Rohn
Sales speed up. This is the more insidious of the two reasons why business owners stumble into money problems. When the revenue of your business increases, your expenses tend to follow. In every business there will be peaks and valleys, and when you dip into a valley, you might experience the expenses outpacing the revenue. When your lifestyle switches, and you become acclimated to the opportunities revenue has provided, it is always hard to go back to how we may have been in the past. Either your ego will keep you from making the adjustments to the dip in sales, you are detached from reality, or you make a decision to adapt. All three of those are choices, and you will have to make a choice to fix this situation.