Digging up this old thread because I got a call to explain what I meant by "Dishwasher does not have a sufficient high loop to prevent drain water siphoning back into dish washer unit.
I have called this out many many times and have never had to explain what I meant.
I provide a photo of the defect and include an arrow demonstrating where the loop should be mounted.
Just wanted to share than no matter how clear you think you are, sometimes someone will not understand.
I know some models do not require a high loop as they have an air gap built in but I call them out every time I see them under the sink.
It’s such an easy fix I am surprised anyone cared.