A while ago I went to Cambodia, and noticed, particularly at the museum in Phnom Penh, that a great number of statues were missing their head and their right hand.
I sort of understand why one would take the head, since you can mount it on its own as a looter, but why the right hand?
I'm sure that this isn't exclusive to Cambodia, and happens in the entire region, but I noticed this specifically in Cambodia.
Cambodia went through many changes in religious beliefs during the Angkor Empire period, from Hindu to Mahayana Buddhism and back again to Hinduism and then eventually to Theraveda Buddhism. One king, Jayavarman VIII, decided he wanted to change back to the old Hindu beliefs, and decapitated or destroyed many Buddhist statues, some estimate up to 10,000.
Hands/arms are easily broken off as they are thin and brittle, I've never noticed it being one particular side, I think you'll find that most are either intact or missing both. It might be possible that as the left hand is considered "dirty" in many Asian cultures the right hands are more prominent and so are more prone to damage.
Other than that, the Kingdom was invaded and sacked by invading armies many times, and a whole lot of stuff got broken or looted. André Malraux tried to steal many statues in the early 20th century, but was arrested. Ironically, he later became France's Minister of Culture.