I never understood the requirement for having to preheat your pipes. The dishwasher has access to a hotline, and a drain. Why wouldn’t it just run the hot water for 60 seconds to ensure it has maximum heat. This would just be a software feature, and cost nothing on their part.
It seems so arcane for the operator to have to do this before running a cycle
There are regulations on water usage for dishwashers. That purge would eat into its water usage.
Yes, purging the cold water manually does exactly the same thing. We live in a flawed world.