Heavily Armoured

Adventurers have a pretty uncanny knack of finding armour that fits them, regardless of their anatomy. The armour of a slender tielfling can fit a bulky dragonborn as both are Medium. It’s odd, but saves some brainpower of considering how much it would cost to bring a suit of chainmail into the blacksmiths to be taken in or let out a few centimeters.

But when you consider truly inhuman adventurers—thri-kreen or aarakocra or merefolk—then that armour would require a lot more adjustment.