Although I'm going off track a little on my own thread, (it's still a still-life though) - I thought I'd post this image as one that I feel just doesn't work. What do you think?
For me it is the (im)balance of tones. The brilliance of the flowers, surrounded by a deep black (and white border strip), renders the middle grays (which occupy a significant amount of space and supports the brilliance above it) sort of life-less.
At least with LF landscape, a bad day of photography can be a good day of exercise.