It's like planning backwards. 1. Determine what you want in life 2. Figure out what your business would need to do to give you that life. 3. Figure out how long it would take you to reach it. 4. Figure out how big of a market it would take each of the years you're planning for. 5. Then see if that market is big enough. Isn't this a much better way to go about planning your business? Shouldn't your business be designed to give you want you want instead of you working yourself to death just hoping for the best?
Now as I said, there are many other reasons too. After graduating from college, I started out in manufacturing as an engineer in a pretty large company and now, 45 years later, retiring as a of Director of Manufacturing, I have discovered an awful lot about business. Not only did I learn and teach a lot about business, I worked with small business owners as well. I've learned that it comes down to this. Too many owners work hard in their business but less on their business.