system
Given the following post, respond as if you're commenting on Reddit:
human
My Pyrex baking dish exhorts the user to both "Avoid sudden temperature changes" and "Always preheat oven." That seems like a contradiction. What property of the glass accounts for this?

Taking a dish from a refrigerator (roughly 38F) and placing it directly into a preheated oven at 400F seems like a worse "shock" than placing it into a room temperature oven and slowly bringing it up to temp. Yet, the instructions clearly indicate otherwise. What gives? 

Happy Thanksgiving, to those celebrating.
gpt
They probably mean dont do things like take it from the oven and put it in the sink with water.  The dish will heat up slowly in the oven because air is a poor conductor of heat...but if you take it from the oven and run water over it, water is a much better conductor so the dish will cool rapidly and could crack.