I am a horrible listener. After almost 30 years I have decided to chalk this up to selfishness. If I'm being honest with myself (and now with everyone else) I guess that deep down I just don't care about 75% of what people say and therefore just don't listen to and process the information. Not my proudest admission, but a true one none the less.
Bearing that admission in mind, people shouldn't go on and on about a subject you know I care NOTHING about. Are my not so subtle hints too subtle? Do I literally have to fall asleep while you're talking to me to drive home the point that I don't care about some subjects?
For instance, telling me that you just bought a Kawasaki Z599S means absolutely NOTHING to me so when I say "ohhhh" with as much excitement as I would if I were in a coma, please don't try to clarify yourself by telling me that it's just like the Kawasaki Z598T but with more horse power - you might as well speak Chinese to me. Which, lets be honest, I wouldn't listen to even if I did understand what you were saying.
This doesn't only apply to motor vehicles, it also applies to computers and movies or TV shows I've never watched or cared to watch EVER.
Telling me the plot of the latest episode of Battlestar Galactica is only going to put me to sleep, NOT induce a conversation. So when I turn around, gnaw on a carrot and fiddle with a calculator just to have SOMETHING else to keep my interest, PLEASE stop talking!
Furthermore, when someone says a punch line from a TV show that everyone gets but me because I didn't care enough to see the show in the first place, please don't take 25 minutes to explain all the nuances of the show to me just so I'll understand the line you told. Believe me, if I care, I'll ask.
This isn't to say that I'm completely heartless and never want to hear things that people have to say. If you talk about my children, disneyland or politics - I promise to listen!