When you have 1 pair , would you like to call with all in ? Do you often raise when having a pair with low card , do you want to catch up a fish on the river?
One pair I can be a little cautious. Even with the high pair, someone could be slow playing a set. I have seen people get all sorts of crazy because they had Ax and the flop came with an Ace and they get beat by someone with a set or 2 pair real easy.