I used to think you needed to stand in line and wait for everyone else to make their way. After all, I learned that in the cafeteria back in school.
Last cruise I took, on Embarkation day, they direct everyone to the buffet as you board. There was a huge line that wasn't moving. I waited a few minutes and when I realized the line wasn't moving I went somewhere else and had rather disappointing pizza. But I found out later the buffet had stations. I didn't wait in that line again.
More and more buffets are arranged by station - there might be a hot food station, a sandwich station, a salad station, an Asian station, etc. Not everyone stops at all those stations. So now I check out how the buffet is set up. If it's by stations, I just go get into the line at that station, if there is one.
However, I was in one buffet many years ago, that was not arranged in stations. It was just a line. I had to wait a while before getting to a plate to get anything. It did irritate me when I was trying to get through the line as quickly as possible so as to not old up those behind me, and these people kept cutting in front of me saying "oh I've already been through the line, I just want to get more of this". Like that somehow made it o.k. to cut the line and hold everyone else up.