A slippery slope argument can also be a slippery slope fallacy. Fallacies are statements that sound reasonable but are actually logically flawed or sometimes even dishonest. Whether or not a slippery slope argument is a fallacy depends on whether it becomes true "necessarily" or just in practice. In many cases it just acts as a warning, and readers have to use common sense as to its truth value. So, strictly speaking, these are fallacies only in the sense that they pretend certain consequences will follow, when in reality the consequences merely may follow.