COTS; Commercial Off The  Shelf.

I have also seen MOTS, for Military Off The Shelf.

Thanks for the info!

Another slightly ridiculous use of MOTS is for 'Modified Off The Shelf', although more specifically for software development - a good example of an oxymoron! It is also an example of an acronym meaning something different, dependent upon which project you are working on.

The software design syllabus I teach refers to MOTS as modified off the shelf which bugs me no end.

Worse is that it refers to COTS as customised off the shelf. FFS people.

Believe me, I understand the frustration.  Years ago I worked in a building that housed numerous US Government agencies.  Each had its own set of acronyms, many of which used the same letters meaning different things (DOD seemed particularly popular, for some reason).  I could almost swear that the motto was "All acronyms, all the time."   At least it provided some entertainment since my coworkers and I spent a fair amount of time coming up with entertaining or off-color phrases to match the acronyms' letters.

No further progress, it seems: https://www.overtdefense.com/2021/07/01/impacts-of-noise-result-in-suspension-of-ajax-vehicle-trials/

AJAX should be cancelled, it’s been a train wreck since TRACER.https://twitter.com/nicholadrummond/status/1410509736433401856?s=20

I regard the UK's record (and probably other nations too, but I'm less familiar with them) of consistent failure in acquiring new equipment with a kind of horrified fascination.

I have a suspicion that with highly complex new systems, so many different firms get involved that there is no-one who has a overall grip of what is going on, or is held accountable when it fails.

I can understand problems occurring with cutting-edge, high tech and therefore high risk projects, but a medium-weight tracked AFV? How can anyone mess that up so badly, then keep carrying on with it as if everything's OK?

What's the one variant of Praeto's Law? 

80% of the cost comes from the last 20% of performance. For a while, people have been demanding that last little bit of performance, and then wonder why they can't afford it.