Use all capitals if an abbreviation is pronounced as the individual letters: BBC, VAT, etc; if it is an acronym (pronounced as a word) spell out with initial capital, eg Nasa, Nato, unless it can be considered to have entered the language as an everyday word, such as awol, laser and, more recently, asbo, pin number and sim card. Note that pdf and plc are lowercase.
Both definitely happen, but this is almost certainly a formal writing versus common vernacular thing.
As for why, I’d guess the pronunciation as a word could be mistaken for the actual word “vat” or, worse, “fat”. Most people want fat on their goods almost as much as they want V.A.T., but now there’s confusion added into the mix.
If nothing else, for the reason already discussed, that sometimes things like VAT are pronounced as a word and sometimes as initials. If you just write it like everyone else in the world who doesn’t write for the Guardian, then it’s just up to the reader whether it’s used as an acronym or an initialism. Nobody at NASA writes “Nasa” and NATO doesn’t use “Nato” (and “pin number” is redundant).
It’s like when the New Yorker uses diacriticals on words with repeated vowels like “coöperate.” Never once has anyone read that and thought “boy, that sure makes that word easier to read.” It just makes you think they’re being pretentious for attention.
That’s the Guardian’s house style for acronyms: https://english.stackexchange.com/questions/51924/proper-capitalization-of-commonly-used-acronyms-and-initialisms
Neat
Huh, I thought VAT was also pronounced as a word
Both definitely happen, but this is almost certainly a formal writing versus common vernacular thing.
As for why, I’d guess the pronunciation as a word could be mistaken for the actual word “vat” or, worse, “fat”. Most people want fat on their goods almost as much as they want V.A.T., but now there’s confusion added into the mix.
Wow. That’s dumb.
If nothing else, for the reason already discussed, that sometimes things like VAT are pronounced as a word and sometimes as initials. If you just write it like everyone else in the world who doesn’t write for the Guardian, then it’s just up to the reader whether it’s used as an acronym or an initialism. Nobody at NASA writes “Nasa” and NATO doesn’t use “Nato” (and “pin number” is redundant).
It’s like when the New Yorker uses diacriticals on words with repeated vowels like “coöperate.” Never once has anyone read that and thought “boy, that sure makes that word easier to read.” It just makes you think they’re being pretentious for attention.
Never eat angry tomatoes
The Economist has a similar standard: https://www.economist.com/sites/default/files/pdfs/style_guide_12.pdf (see the ‘pronounceable abbreviations’ section, for instance)