I think I'd be more likely to continue riding through the winter if it weren't so dark when I leave for work beginning at this time of year. When I drive to work in the mornings lately, I struggle to see through my frosty windows, and if I don't keep spraying defroster fluid on them, I can lose practically all visibility.
I don't want to be a cyclist on the road with people in cars having this same problem. Especially if they are on their phones complaining to their friends about it.
But to the point of this thread, I was just talking to my wife yesterday about how, within the past ten years, I've gone from looking forward to bundling up for a brisk winter ride to having absolutely no ambition to do so at all .