We lost the Mars Climate Orbiter in 1999 because Lockheed Martin supplied a part that output results in pound-seconds and then that number was fed in to a NASA part that interpreted it as Newton-seconds.[1] Having US engineers speak a different language than all of the other engineers in the world imposes real, non-negligible costs for data checking and risks of failure for any project that might interact with non-US-centered expectations.

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