...well NASA (or its supplier) did try - the infamous Mars Orbiter crash[0]:

The primary cause of this discrepancy was that one piece of ground software supplied by Lockheed Martin produced results in a United States customary unit, contrary to its Software Interface Specification (SIS), while a second system, supplied by NASA, expected those results to be in SI units, in accordance with the SIS.

[0]: https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_...