Other reasons for failure
The learning curve is overlooked
- Or the expected degree of repetition is not realized
- Because the work is planned differently
Outside supplier or service costs increase
- Because they have not been frozen by an agreement
Waste and spoilage are not factored in
- Perhaps because of unanticipated rework
The estimate has been taken "as-is"
- Without conversion to a project budget
- As described in Issacon #1336