[dreamcompiler]

It's sort of similar with very hot things. I'm a blacksmith, and I rarely wear gloves. Steel is a poor conductor of heat, so if you grab it just a few inches away from the red-hot end you're fine. If you hold it too close, you realize it instantly and let go before any serious damage happens. But if you wear cotton gloves for a while, you'll grab the steel closer to the heat without realizing how hot it is, and then the accumulated sweat inside the glove suddenly vaporizes, and you get a nasty steam burn before you can get the glove off.

[samfriedman]

Similar thing working in a kitchen: always grab things out of the oven with a dry towel. Use a wet towel once and you'll never make that mistake again: the steam exploding against your skin will hurt you a lot more than the metal on your bare skin would have.

[jonhendry18]

Similar with calfskin welding gloves. They'll protect you, but if you grab something really hot, after a moment you end up with a really hot piece of calfskin against your skin. And when you let go of the hot metal object, you still have the hot calfskin against your skin.