The Arabic word that corresponds to "human being" is Insan. This word takes its root from the word Nisyan, which literally means "forgetfulness". Man is undeniably a very forgetful creature! This trait of forgetfulness has two sides to it; there's a good side and a bad side.
The good side of this attribute has been well-explained to us by Imam Sadiq (peace be upon him), who is narrated to have said: "Even a greater boon than memory is forgetfulness, without which man would not found solace in any affliction, nor would have ever gotten clear of frustration, nor could have gotten rid of malice. He would have failed to relish anything of the world's goods because of insistent memories of affliction, nor could he ever have entertained any hope of weakening of his sovereign's attention or the envy of the envious. Don't you see how the contrary faculties of memory and forgetfulness have been created in man, each ordained with a definite purpose?"
Hence we can see how forgetfulness can be a blessing for us.
The bad side to being forgetful is quite self-explanatory. When was the last time you could not recall an important mathematical or scientific formula for your exam, or when you kept a very precious item of yours in such a safe spot that you yourself could not remember where it was? There are several examples of how our forgetfulness can mess up our day-to-day lives.
However, a higher degree of forgetfulness is the one that can ruin one's life as well as afterlife (the permanent abode). This is definitely the kind of forgetfulness that one should try to keep away from by all means. It distances one from Allah and His special servants and leaves one in the state of absolute desolation! Our Prophet (peace be upon him and his progeny) has said, "Every child is born on the Fitra (innate disposition towards the Truth), and it is his parents who make him a Jew or a Christian." This tells us that Islam is a religion that is built within our very existence; ignorance towards it is an outcome of forgetfulness. In his book Self-Building, Ayatollah Ibrahim Amini explains this problem as follows: "If the imperious-self and animal-self took over control of bodily affairs, the wisdom and human-self are subdued and become isolated, in which case a man gradually takes distance from God and human values, falling ultimately into deep and dark valleys of ignorance. He forgets his human-self (i.e. humanism) and recognizes in its place his unconscious self (i.e. animalism)." Therefore, forgetfulness of Allah, and eventually of our "selves" is a result we see when the spiritual and human "self" of man loses against his animal self.
Man is in dire need to be constantly reminded of his true reality and his true life, which is his spiritual life. If man gets swayed away continuously from his main purpose of life, it is due to excessive materialistic and worldly engagements. It is for this very reason that Islam stresses on the importance of matters of practice and the significance of its ritualistic acts. These actions are often repetitive in nature because they are our reminders. Let us take for instance the daily ritual prayers (Salat) that all of us are obligated to offer five times a day. The role of Salat is considered to be more significant than any other act of worship, because it is the most powerful reminder of our submission towards our Omnipotent Master and Creator. Our Salat is like our checkpoint through which we pass five times a day in order to ward off illicit and sinful behavior from ourselves. Similarly, all other practical and obligatory actions, the recitation of the Holy Qur'an, the supererogatory acts of worship, our Azadari and mourning sessions on Imam al-Hussain (peace be upon him) and the tragedy of Karbala are all blessings and should serve as great reminders for our weak and forgetful souls!