Each season focuses on sociopaths in different parts of the system. The justice system, the waterfront, the schools, and finally the media. Different people from inside those institutions have commented they were the most realistic portrayals of the institutions they had ever seen on TV. It is actually Barack Obama's favorite TV show. However, Showtime actually refused to take up the show due to its pessimism. This show has a more accurate portrayal of sociopathy in reality in contrast to shows like Sopranos or Dexter.
Lester: Tell me someting Jimmy, how do you think it all ends?
McNulty: What do you mean?
Lester: A parade? A gold watch? A shining Jimmy-McNulty-day moment, when you bring in a case sooooo sweet everybody gets together and says, "Aw, shit! He was right all along. Should've listened to the man." The job will not save you, Jimmy. It won't make you whole, it won't fill your ass up.
McNulty: I dunno, a good case—
Lester: Ends. They all end. The handcuffs go click and it's over. The next morning, it's just you in your room with yourself.
McNulty: Until the next case.
Lester: Boooooy, you need something else outside of this here.
McNulty: Like what, dollhouse miniatures?
Lester: Hey, hey, hey, a life. A life, Jimmy. You know what that is? It's the shit that happens while you're waiting for moments that never come.
Lester: A parade? A gold watch? A shining Jimmy-McNulty-day moment, when you bring in a case sooooo sweet everybody gets together and says, "Aw, shit! He was right all along. Should've listened to the man." The job will not save you, Jimmy. It won't make you whole, it won't fill your ass up.
McNulty: I dunno, a good case—
Lester: Ends. They all end. The handcuffs go click and it's over. The next morning, it's just you in your room with yourself.
McNulty: Until the next case.
Lester: Boooooy, you need something else outside of this here.
McNulty: Like what, dollhouse miniatures?
Lester: Hey, hey, hey, a life. A life, Jimmy. You know what that is? It's the shit that happens while you're waiting for moments that never come.