You sign a contract to design a logo for $2,000. You estimate it will take 20 hours. Your expected freelance hourly rate is $100/hr.
The client then asks for "just one more concept" and wants to jump on three unexpected hour-long Zoom calls. You spend an extra 8 hours of unbilled time appeasing them.
Actual Rate = $2,000 / 28 hours = $71 per hour Lost Profit = 8 extra hours × $100 = $800 lost
You essentially gave the client $800 worth of your time for free because you did not cap revisions or charge for extra meetings in your freelance contract.