Optimisation
Why can optimisation save you money?
What is optimisation?

Optimisation is a method of improving the accuracy of an instrument by  adjustment.  Unless you are a politician there is no such thing as absolutely right and this is certainly the case in measurement.

There are three good reasons why some companies do not optimise instruments as part of the calibration process.
1. It takes time.
2. It is difficult because improving the performance on one range can upset another range.
3. The company can charge for the optimisation as an extra and sometimes charge again for the subsequent calibration.