Reading up on bain-maries, it becomes clear that the names Marie or Mary became attributed to what we now know to be the bain-marie at the time of its invention. I lament this because I think a word like bain-rochelle is far catchier and would boost sales of the item exponentially.
But as for Lazy Susan, Wikipedia claims there’s no concrete evidence as to why Susan has emerged the top choice for naming the revolving tabletop. What will they think of next? An automated microwave (Active Betty)? A compartmentalised container for holding multiple cereals (All-Purpose Claire)?