The selective coloring is very weak since the colored subject only contributes a tiny portion to the overall photo.
It is a good example of why most times selective coloring doesn't work very well.
The black and white portion of the image lacks contrast and tonal depth. My guess it was simple desaturated, rather than converted which also makes it as weak as the tiny, selectively colored flag.
Compositionally the photo could be strengthened somewhat if about 1/3 is cropped off the top because the mountain in the background is not adding much beyond some distraction to the photo.