Taste is so subjective, I’m sure most people will have something named here.
for me, I’m not a fan of :
decking, it never is maintained right, and always looks a bit faded and gets slippy in winter.
charcoal or blue toned greys, I find it a bit cold.
purple, I just don’t like the colour.
Cheap laminate flooring, you can always tell and it always looks cold.
lack of a coffee table, just sofas pushed up against the walls and a big space in the middle of the room
coloured bedding, plain white for me.
laminate work tops. Stone always looks better, be it granite, quartz etc or real wood.
orange knotty pine.
lots of ornaments , clutter like too many books, cd’s, dvd;s etc and a display cabinet.
fridges, washing machine, dishwasher not integrated in a kitchen,
astroturf in the garden , that’s a poor show on so many levels
lack of anything personal , like family photos on the side or a couple of books out.
sparse soft furnishings , like thin flat cushions on the sofa. All matchy matchy and thought to bring a “pop” of colour to an otherwise drab sofa
cheap wallpaper from home base or b&q, with big patterns in it, like flowers or swirls. I love wallpaper but it’s got to be done right.
shiny brown leather sofas. They suck the light out the room,
curtains unless done properly, full length, luxurious, voluminous
however these are just my taste, I’m sure folks wouldn’t like much of how I chose to decorate.