When a dishwasher uses hot water from a hot water pipe, does it know it
should wait till the hot water runs hot, or does it just go ahead and get
whatever comes out of the pipe?

If a dishwasher has the capability of heating its own water, would it make
sense to connect it to the cold water? If it gets cold water from the hot
water pipe, then, by the time it finishes getting the water it wants, the
hot water pipe would start to get hot, which would be wasted while waiting
for the dishwasher to use it again. That problem would be solved by
connecting it to cold instead of hot, so no hot would ever be wasted.
Right?