#1 - blown highlights, esp the yellows and sharpening is causing artifacting.
#2 - harsh shadows created by the sun. Reflector or fill flash would have helped. The messy shirt could be cleaned up in post.
#3 - Selective color not particularly useful here and it really ruins what I think might have been a very sharp image. You can definitely tell where there was some cloning/healing done in the background. Compression causing artifacting here as well.