Metrics are only as good as they reflect the thing you are trying to improve. If you want to improve how much profit you can get each job because your sales staff can only get 30 sells a quarter. Then tracking per job would be great. If profit is limited by hours worked then you should hire another employee.

Time is money. So it really comes down to what is most efficient. For instance you could spend 200 hours learning to make a nice webpage. Or you can work 40 hours at a 8-5 job, pay to have the webpage created and spend 160 hours working on your product.

The flip side is treat it like gambling. Only put up what you can afford to lose. If your 8-5 income is a fixed value and you have free hours. Then spending the time to learn creating a webpage could be the most efficient way of making it to the goal.