> Come to think of it, if there is a latching door on the detergent tray, your dishwasher definitely has a prewash cycle, or else they’d skip the door entirely
Alec also mentions this briefly in the linked video; if manufacturers could avoid the cost of a latching mechanism, they absolutely would. Its presence means a pre-wash cycle exists.
My GE seems to skip the prewash cycle on the default setting for whatever reason. It does use a prewash on its "heavy duty" cycle though. Incidentally "heavy duty" also works infinitely better, with no more damage done to my dishes. YMMV of course.