Also, I’m way too lazy to look it up right now, but I’m quite certain I’ve heard of dishwashers that run the hot water for a little bit before letting it fill the basin. Like, I’m pretty sure this sort of thing is commonplace.

It’s not like the engineers for heaterless dishwashers are just too stupid to realize there’s an obvious workaround for having to purge the line before filling the basin. Especially when the performance is so much measurably better when you do it.

Like I said though, it’s a guess. It’s also possible efficiency certifications ding you for the excess water use.