drunken tourists who couldn't even be able to control their risky skiing if they were sober. self appointed free style skiers who ski backwards in kids classes. People who can barely do a proper turn thinking they should go off piste. Not only do they not check the avalanche risk before they ski/fall down the mountain. Most times they decide to ski through the wildlife protection zone (fresh untouched snow..). No matter they wake marmots from their winter sleep or scare chamoises so much they jump of the cliffs.
but fortunately there are very few unhappy moments during winter-season :)