It makes changes to your system, does not tell you what it is doing, or what it did and there is no way I can find to undo anything it did.. I never, ever gave Avast permission to do ANYTHING to my machine without telling me, and in the case of removing things, I want to be ASKED first.
It does not matter that I am part of the Admins group for a rather large company, it should not be doing that to ANYONE's machine without asking.