We like to optimize for efficiency, and commonly used phrases are a perfect candidate for it – it takes less than a second, and you have a whole bunch of weird looking acronyms. But they are here to help – everybody knows what it means, and it saves us time and space (so we don’t write “Modern Improvements Mission”, just using “MIM”. What about MIM?). And it does help! It works perfectly for some time, until time passes and new people come – it is a delay-action bomb.