The Small Business Start-Up Guide discusses the need to stick with it during the initial stages of a new small business:
Then comes more twelve- and fourteen-hour work days, seven-day work weeks, and self-sacrifices that must be endured for whatever period of time it takes you to be successful. And once, "there" - wherever it is your goals take you - you must continually strive for better and more success.
It takes a disproportioniate amount of time to get a new small business off the ground. That's why it's important to know why and what you're doing because only time will tell if success has been achieved.