When you finish a show or movie on Netflix, the site requests that you give it between one and five stars, based on how much you enjoyed it. You're not being asked to rate that content for kicks, or so that you can later reminisce about how much you liked a certain film: Rather, Netflix has spent many years improving its recommendation engine, even offering a $1 million prize for anyone who could up the accuracy of Netflix recommendations by 10 percent.
At this point, the Netflix recommendation engine is pretty darn accurate -- it takes into account your own ratings as well as the viewing habits of those similar to you. Basically, the more films you rate, the more you're likely to enjoy a Netflix recommendation. If you constantly find yourself frustrated that there's nothing on Netflix, take a half hour or so and knock out a few hundred ratings on the "Taste Profile" section of the site, and make sure you've filled in your genre preferences, too.
Finally, if Netflix persists in recommending a title that you're just never going to watch -- for me, that would be "The Lincoln Lawyer" -- remember that you can click on the "Not Interested" button on any film's homepage and it will disappear from your recommendations page while simultaneously smartening up your future recs.