Some of the reasons for this include the lack of accountability and the general predilection for mischief that Shakespeare attributes to men in general.
In the historical dramas, such as "Henry IV," much more than in the comedy, the characters are prone to making mistakes also because their individual weaknesses as human beings. As human beings, they face not only the external factors and challenges that create the appropriate environment for making mistakes, but also their own conscience and the need to make sensible decisions that actually matter.
One should also point out that in some of the other plays, Shakespeare plays an equal amount of blame on the shoulders of female characters as well. Most notably, tragedies such as "Hamlet" or "Othello" are examples in that sense. Women share the blame and the volume of mistakes that eventually lead to the downfall of the main characters.
Bibliography
1. Shakespeare, William. Henry IV. The Oxford Shakespeare. Oxford University Press. 1987.
2. Shakespeare, William. Henry V. Oxford School Shakespeare. Oxford University Press. 1995.
3. Shakespeare, William. A Midsummer Night's Dream....
Acclaim Books. 1997
4. Rabkin, Norman. Shakespeare and the Problem of Meaning. Chicago: University of Chicago Press, 1981
5 F.E. Halliday, A Shakespeare Companion 1564-1964, Baltimore, Penguin, 1964.
6. Kastan, David Scott (ed.) "King Henry IV Part 1" The Arden Shakespeare: Third Series Thompson Learning 2002
7. Sisk, J.P. "Prince Hal and the Specialists." Shakespeare Quarterly 28 (1977)
8. Shakespeare, William. A Midsummer Night's Dream. The Riverside Shakespeare. Ed. G. Blakemore Evans and J.J.M. Tobin. Boston: Houghton Mifflin, 1997
9. http://www.theatrehistory.com/british/midsummer001.html Last retrieved on November 11, 2009
10. Bloomfield, Jem. Fairies in Midsummer Night's Dream. 2007. On the Internet at http://shakespeareantheatre.suite101.com/article.cfm/fairies_in_midsummer_nights_dream. Last retrieved on November 11, 2009
Shakespeare, William. Henry IV. The Oxford Shakespeare. Oxford University Press. 1987.
Shakespeare, William. Henry V. Oxford School Shakespeare. Oxford University Press. 1995.
Shakespeare, William. A Midsummer Night's Dream. Acclaim Books. 1997
