Human personality gets formed by numerous amount of factors starting from the day of birth (or conceiving probably). To name a minimum few they are, upbringing by parents, neighborhood, education, friends, place, etc. etc. To stress again, this is a bare minimum list, each and every second of life impacts us in different ways. It is up to the individual how he perceives the scenarios of his/her life and what he/she/it understands from those scenarios. It is practically next-to-impossible to list all the factors which have made up the personality of person. Because of these huge amount of factors involved, a person understanding themselves itself is a big deal, live alone understanding of other person. Lot of philosophies have written loads of text on the matter of understanding oneself.
In spite of all these difficulties in understanding a person, I must admit, women have some special ability to understand their man. Some examples that I have seen are, women typically know the reason of their man being angry (Man himself might not know), women knows the needs of their man better than man himself, Women know the likings/disliking of their man, Women can pick-up cloths which a man will like (but the opposite probably is never true) etc. etc. I am sure each of you will have more examples for yourself to ponder upon. Despite of this understanding of their man, women, I have seen haven't shown much of understanding of themselves. But, in case of the children, women show an amazing clarity of understanding, which a man never can even dream of achieving I guess. This whole issue of Women's strength and weakness of understanding looks very complex.
As usual, I cannot stop myself from analyzing the reasons behind such great powers of the women.
From the days of hunter/gatherer humans, typical structure of a family is, Man has the responsibility of earning food, and woman has the responsibility of managing the family. Because of the responsibility, a typical man is always outside the house figuring out ways to earn the food for the family. (For most of the human life on earth, humans had to use physical energy to earn their food) When a man is home, typical objective of a man is to have rest, so that he can be ready for earning food the next day. Whereas typical woman, had the responsibility of taking care of family. Managing a family meant, managing the resources (food, money, house, utilities etc.) and managing the people (children, Man). Because of this responsibility, women have always put an effort to understand their Man, children, so that their needs are satisfied for the effective functioning of the family. Whereas, a man has never had a need to understand the woman to perform his duties for the family, only thing he had to know was the ways to earn his food. The balance of the family is maintained because of this, and the whole family lived happily.
For thousands of years, the responsibilities of a family has been structured in this way. And hence, women have built the skills needed to manage their family effectively. One of the skill being, understanding the people, especially the husband, they have mastered effectively. Probably over the years some of these skills have got into the gene of a women. Lately, there has been an argument for women making better managers than Men in corporate world. I guess the reason is, Women have been performing the role of managing the resources and people in a house-hold from thousand of years, it is very natural that they extend these skills to manage a corporate.
Over last 300 years, with the industrial revolution and all the technological innovations which have happened in the world, the need for physical effort to produce food has decreased considerably (The decrease has been continuously happening from last 3000 years starting with invention of wheel etc. But the industrial revolution has reduced the physical effort exponentially). With the advent of mechanization in clothing, making utensils, medicine, etc. in the society, the effort needed to manage an house-hold has reduced considerably also. The effort needed by both a Man and Woman to perform their duties in a family has been reduced considerably over last 2 centuries. Hence both Man and woman have put effort to re-define their roles in the family. The effect is clearly visible with the changing social structures, husband and wife working, decrease in importance of broader family, etc.
With the changing roles, the need for an Man for understanding his wife has increased exponentially over last 100 years. I believe, in today's world, more and more men are putting effort to understand their wife. I need to say, I have seen some who have even succeeded to a very large extent. Today's women, also expect their man to put effort to understand them, and hence the failure of a Man is more visible, when they fail and say "I do not understand my wife" in frustration.
In the historical days, woman looked for qualities like, ability to earn, strength, social status etc. in a man for choosing a husband. Whereas man looked at the qualities related to managing the family in a woman. With the nature of the world changing, today, both woman and man look at the qualities of "understanding, compatibility" in marriage.
Though, woman have head start of thousands of years in skills of understanding people, Man is making all efforts to learn the skills and continuously improve upon the skills, to live in the changed world. Best of luck for all Men! Failure is the stepping stone for success.