A revert may be done for a wide variety of reasons, including: fixing errors introduced by previous edits; restoring the material to a state that was not contentious until new disputes can be resolved; undoing scope creep; regression testing; and even petty malice, vandalistic intent, or personal unhappiness with the author of a previous change. While the process is generally agreed to be a sound and sometimes necessary one, particular instantiations of its use may be at least as controversial as the changes being reverted.