False teachers do not submit to Jesus authority when it comes to dealing with “problem people” in their church. (This is the stick they use to expel the “sinning brother" without going through the process Jesus commanded. Some churches have adopted false teachings and some of those churches have included the false doctrine in their statement of faith; then they use that proclamation to stifle all future discussion and debate. Like the pharisees of old, they cannot believe that they may have misunderstood the scriptures on some important point. None of us are infallible. We should love truth more than our doctrines. We must be willing to re-examine the scriptures as often as someone challenges something we believe with the claim that, "the Bible teaches." There are no excuses for ignoring the outline Jesus gave for dealing with problem people in the Church. According to Jesus, there are no exceptions to the rule. If the people in each individual church followed what Jesus outlined when dealing with people who taught "doctrinal errors," errors would be identified and doctrines would be improved. If throughout church history “heretics” were dealt with according to the pattern Jesus outlined, the church would be in much better shape today.)
Now having said that, I want to turn to an issue which is now dividing the Church. (The question is, "Is the division necessary or unnecessary?")
The man in the following video may fit the category of a false teacher. I can't see how he can honestly come to some of his conclusions. I don't agree with many of the things he says. His message in the following video is abrasive. It's so abrasive that I wasn't going to share it on this site. But I decided to because on this particular issue he makes some very important points that Christians ought to carefully consider. He certainly sums up what many people think (see the comments on YouTube).
What he says about this doctrine causing more people to reject God than all the wars and all the oppressive regimes combined may have some truth to it. Japan might have become a predominantly Christian country if it was not for that doctrine (see the video below). Not only has the doctrine caused many to doubt God's goodness, it has been the primary justification for persecution of heretics and Christians by other "Christians." See "A Legacy of Fear and Persecution" in Thomas Talbott's book The Inescapable Love of God.
Nowhere in the Bible does it say that a person has to accept a particular view about the nature, purpose and duration of hell to enter into God's Kingdom. So people who teach that Jesus is the only way to God, but also teach eternal torment, or conditional mortality, or universal reconciliation should not be regarded as false teachers.