Sweaty hands in cold gloves. Then the barfies.

Wet hands get cold first.

A glove is only as warm as the hand inside it is dry. Hands sweat on the approach and on the hard moves, the liner soaks, and the cold gets into wet skin far faster than dry. The barfies, that rewarming pain at the top of a pitch, comes from hands that went cold and clamped down on blood flow while you gripped the tools.

Dry hands the night before keep the liners drier longer. A looser grip keeps blood moving. Repair at the end of the day puts water back into knuckles that spent eight hours in dry, freezing air. Same cream climbers use on summer rock, put to work in winter.