When they start dragging in bits of wallpaper that puts up the red flags for me. I've had bathroom tiles, kitchen cabinet doors......
That approach is far too literal and simplistic IMHO. You have to take the whole room into consideration, not the details.
I always thought a frame should provide a pleasing transition between the image and it's surroundings. But people get the idea that "we have oak furniture
ergo all the frames in the room should be oak", it's not a good design principle. A frame should harmonise with the surroundings, not try to blend in.
Then we get on to colour. The times people have said they want a red or whatever element in a mount to 'pick up' a similar colour in the image. What they mean by 'pick up' I have never been able to fathom out. If they want a particular colour the stand out more in an image, they want a complementary colour. Not the same one, which will have the opposite effect to what they seek to achieve.