A calibration gives you feedback about a measurement instrument's metrological behavior. Is it precise? Is it repeatable? Does it have linear characteristics? These questions can only be answered once a calibration has been performed. After a second or third calibration (ideally carried out by the same calibration provider), confidence in the instrument can also be proven by data: this creates the basis for further decisions on issues such as recalibration intervals. All measurement instruments are exposed to environmental influences throughout their lifetimes. Wear and tear, an overload or a crash can damage your equipment or change its properties: these events could falsify the data you obtain – but instrument users might not even be aware of such problems.
For all these reasons, periodic calibrations are essential to ensure that your measurement equipment operates precisely and reliably.