Most fabrication shops prepare careful quotes, but very few go back and compare them with what actually happened in production. It takes a few minutes per job, and over time it builds a valuable body of data.
What the comparison reveals
Comparing hours quoted against hours worked, and materials estimated against materials actually consumed, brings out patterns that otherwise stay invisible: a process that consistently takes longer than estimated, real waste higher than the figure used in the sums, a product type that always generates changes mid-build.
From isolated incident to structural correction
A single variance can be a one-off — a surprise, an occasional mistake. But if the same variance repeats across several similar jobs, the parameter used in the quote (processing time, waste percentage) no longer reflects reality, and needs correcting for every future quote in that category.
A light habit that pays over time
You do not need a complex system: record real hours and materials at the end of the job, and periodically compare them with what was quoted. Over time that discipline builds calculation parameters ever closer to reality — and quotes you can trust, without inflating margins to cover an uncertainty you could instead reduce with data.