Why do people crank up the AC in offices when it is hot outside?

[MagpiePi]

I'm in the office today in jeans and a sweatshirt with my sleeves pulled down over my hands because I'm bloody freezing and the AC is blowing out cold air down the back of my neck.

I know - and certainly when it gets really hot a/c is wonderful.

But late teens/early twenties as it was here? No. That's both ridiculous and a complete waste of electricity - and yet there it was, blasting away. Fortunately I'd taken a cardigan.

That is pretty chilly inside I think for most