The protagonist, Don Quixote, left his business and sold much of his estate in order to acquire a library of some three hundred books pertaining to knights and knighthood. He pored over these books night and day; and (as the author makes mention) "in the end, through his little sleep and much reading, he dried up his brains in such sort as he wholly lost his judgment." After this misfortune, he began believing himself to be a knight. So Don Quixote persuaded the ignorant and fearful Sancho Panza to serve as his squire on adventures in which he entered some righteous and some unrighteous causes, always touting his most illustrious Lady Dulcinea of Toboso.
Both Don Quixote and his squire have obvious weaknesses that make them unfit role models. The book mentions that Quixote was in the habit of cursing and swearing, although the author was decent enough to omit the actual words. Sancho Panza was no better: in fact, he had two great faults. He left his family to fend for themselves while he went traipsing around the countryside; and his reason was also faulty, being that he was eager to acquire an island to rule. However, these imperfections were not entirely useless. They helped many people to see the ridiculousness of fantasizing knights and castles when they were not even still in existence. Thus, Miguel de Cervantes aptly performed his task of satirizing the popular reading of his day. Soon after the publication of Don Quixote of the Mancha, the popularity of its many silly predecessors began to decline; yet Don Quixote remains popular today due to the hilarity of several escapades, the most notable of these being his fight with the windmills.
Overall, the primary purpose of this book expired soon after it was written. I would not recommend that others read the entire book since it does not have beneficial morals incorporated into each adventure. That is not to say, however, that none of it should be read. There are several passages that should continue in popularity due to the moral lessons hidden within their chaos.