> If you're consulting I would suggest not billing by time but by value provided. If you're doing that then accurate estimates become even more important. If y

> If you're consulting I would suggest not billing by time but by value provided. If you're doing that then accurate estimates become even more important. If you are billing by time and things take longer than you expect then after a while your customer is going to get angry and that's going to have consequences. But if you are billing by value then if things your employees are working on take longer, you're eventually going to make a loss on the project as a company. So you need to price the value right, and that involves knowing how long things will take in advance.