If your goal is to build a more valuable company, stop selling your time. 

Billing by the hour or day means customers are renting your time rather than buying a result, which means that your business model lacks leverage. To grow, you need to either work harder or hire more people. Since it can take months to ramp up new employees, fast growth is just about impossible.

One of the eight factors that acquirers look for in the businesses they invest in is your company's Growth Potential. Simply put, they want to know how fast they could grow your business, and nothing diminishes your Growth Potential more than selling your time.