As an example, we preach and teach as a sure and primary doctrine that our Messiah will come again for us. This fact we can all rally around and rejoice in hope. However, the exact when and how of Messiah's coming is left open to various interpretations. We can teach the possibilities, but we cannot arrive at many absolutes. The when and how cannot be for us a primary doctrine.
Unfulfilled prophecy has the potential of various perspectives and meanings.
Elevating a prophetic perspective to the level of absolute doctrine only results in quarreling over non-essentials of faith. In order to keep the unity of faith, those words which come from the mouth of the L-RD as absolute commandments must remain the highest priorities of doctrine. This does not mean that we should not discuss the possibilities of prophecies in the household of faith, but only to be careful to discern those things which are essential from those that are not essential. In other words, belief in a perspective of unfulfilled prophecy is never to be required, while obedience to the commandments is required. An interpretation of unfulfilled prophecy is never an essential of faith.