Quran is the last word or Book of Allah which He revealed bit by during his life time unto the Holy Prophet (SAW) according to the prevalent circumstances of the life time of Holy prophet (SAW). It took about 23 years for its revelation. The Holy prophet (SAW) narrated it as and when revealed.
It is free from any kind of doubts on short coming. Muslims have to believe in every word of Quran, it’s every Verse and its Surats. The orders of Allah conveyed through them have to be strictly followed. If we don’t act accordingly then we are guilty of transgression of the commands of Allah.
Allah reveals in Surah Al Maidah (The Table Spread) as under:
Those who do not decide according to the commandments of Allah, they are infidels. In Holy Quran some commandment are fully illustrated and all such things are elaborated in them which may be needed in all times to come by the future generations. In other words these commandments pertain to the spiritual, physical Material and mental prosperity of Muslims.