They openly deny that Jesus Christ was God. You may think that the JW's are at your door because they care about your soul, but if they are honest they will admit that one of the requirements for their salvation is a certain number of hours spent door to door calling. Mormons require that their young men spend two full years wearing black suits and ties and riding bicycles door to door as well. It might sound like I am picking only on Mormons and Jehovah's Witnesses, but it is just that they both illustrate all four errors so well. Instead of following Jesus Christ alone the Mormons follow Joseph Smith and the Jehovah's Witnesses follow Judge Joseph Franklin Rutherford and Charles Taze Russell.
Some cults have living dynamic leaders who control every aspect of their followers lives.
Jim Jones comes to mind. All cults and their respective leaders major on the minors such as the supposed evils of the Easter Bunny or Santa Claus, make up etc. The fact that there are so many cults proves one thing. Counterfeit money is a copy of something real and valuable. The fact that Christianity has been so counterfeited so much and so often is living proof that it is real and of great value.