When I worked in the medical field, doctors would occasionally visit unannounced. We were required to wear a shirt and tie, with an available jacket, at all times.
I remember my brother in law, who worked in very senior position in a large UK financial institution that "holidays are when you can go into the office and take your suit jacket off".
I don't even own a suit :-)
Edit: A few years back I turned down a second interview at the same organisation after they insisted I turn up "in standard business attire" - i.e. a suit.
"holidays are when you can go into the office and take your suit jacket off"
Last time I went on holiday, I took a tailored suit and dressed smarter than I do at work. Three-piece suit (typically I wore just the waistcoat; done right, that looks smarter than the jacket), tailored shirt to go with it.
When it's your own choice to look sharp, it's a whole different game.
