if you play poker long enough with the same people, you realize after a while that some players always win while others like me just don't know how to really take advantage of the play to last. I generally can kill off a few players so I start quite big, but never really know when to drag things out well enough. Not for me, at least I can admit it:)
Usually the big players in poker tournaments happens to be the same people over and over again, obviously there are times when one lucky person goes very far or even maybe win but if you check tournaments that happens in periods, like weekly or monthly or even yearly you will see the same names over and over again.
The reason for that is exactly what you mentioned, the really good ones knows how to play the table, which means they check the players and not the cards and that is the biggest trick. If you check the players and see what kind of players they are you will end up with learning their own moves and you can use their moves against them. Most big poker players will tell you that what card they have doesn't matter, what card other person has doesn't matter neither, as long as you know them you will come out on top.