Very interesting question, Michael !
The point of view / subject raised by Ken (Bajaespuma) is equally very interesting.
There exist a photo of myself taken next to our Hoover washer, from 1966.
IIRC, my mom started to use a small Hoover twin tub washer back in 1965 (the year of my birth). As a person she's been very courageous because she's gone through so many health problems, most notably tuberculosis at young age which resulted in the removal of one of the lungs followed by half-a-year stay in a sanatarium. The tiny portable washing machine was bought brand new; back then, the unit came to Canada as an import from England (it was manufactured by Hoover in Wales, right before twin tub machines began to be manufactued in Hamilton). In 1965, for about 150 bucks you got one of those BNIB Hoover machines--ready for the laundry tasks!
Some friends of mine used to ask, jockingly, 'why don't you collect stamps instead of washing machines?' ...'It would take far less space in your dwelling!' ...To what I always answer that I personally have 'no thrill' in collecting stamps or coins. I'm a passionate in twin tubs, in particular. Why? For some reasons, the twin tub types of washing machines have always been part of my childhood. So much so as to become 'obsessive'. Not only we had that noisy but so practical Hoover in the home, but also my grand ma, a couple of my aunts, one cousin as well as a close neighbor, had one of the various brands who actually made those portable twinnies. That kind of a machine was a very popular concept and made twin tubs big sellers during those years. It was portable, enough small, lighter than the huge fully automatic Maytag (who, BTW, did also manufacture their own twin tub, the small but efficient A-50 Porta-Washer)...
Suffering from severe anxiety, I know too well what obsessional-compulsive is all about. However, where exactly sits 'the line'? That imaginary red line which separates obsession from the passion for something. Me? It is that love for the vintage appliances--or furnitures--of the past (I'd rather say of MY past). That period (up to the late 1980s) whence you bought something with absolutely no planned obsolecence in mind; when things used to be built solid and made to last forever, so to speak. I know I might sound like an old nostalgic buff who wants to resurrect the past. But, hey, those years were the results of pioneering R & D which began well before the Second World War, from Nikola Tesla to Henry Dreyfuss.
In sum, I'd say my interest in washing machines--and other vintage home appliances, such as vacuum cleaners--is part obsession part passion, and simply for the pleasure of collecting things. Why not washing machines? ...Or stamps!! : )