Fully Submergable
Not sure who started it but it became a huge trend for electrical cooking appliances that for the most part is still going strong.
Then and how housewives and others were getting sort of a "ewwwwwwwwwwww"factor from not being able to wash electircal skillets, fry pans, griddles and so forth. Merely wiping them down with a cloth wasn't up everyone's street, nor was the delicate dance to wash the thing while preventing water from getting inside.