ANSWER: The Bible does not reveal the reason. Some hold that it was because of the continuous idolatry of the tribe of Dan as described in Judges 18:30-31. However, this, and all other suggestions, are nothing but speculation. Though there is no harm in wondering about such matters, undue consideration should not be given to the things God has not revealed, but rather to those things He has revealed (Deuteronomy 29:29).