>> And if that estimate isn't within 10-15% (the usual error bars) of the actual project duration/billable hours, there's going to be a problem. >Alternatively

>> And if that estimate isn't within 10-15% (the usual error bars) of the actual project duration/billable hours, there's going to be a problem. >Alternatively, if you’re doing project-based billing instead of hourly billing then getting your estimates wrong can result in a lower effective pay rate for the job. Exactly. That's certainly a problem, just not one that the the client is going to complain about.