Zane’s doorbell goes “ding dong”.
You know, when you press the doorbell button, it first goes “ding”, and then after you’ve let go, it goes “dong”? When I was little, it was hilarious to keep the finger pressed on the button for a few seconds longer than necessary or sensible, resulting in “ding… … … dong”. It was pretty childish and grew old (and annoying) very fast, of couse. I don’t do it anymore.
This is Sylar ringing Zane’s doorbell.
This is Mohinder ringing Zane’s doorbell.
As you can observe, Sylar’s ding dong is much longer than Mohinder’s! (I just really wanted to write that sentence.) ERGO, he kept his finger on the doorbell for a moment, maybe because his mind wandered off and he forgot he was in the middle of ringing a doorbell… Or because he’s completely immature.