Sometimes we have a favourite opponent (or 'customer') who we invariably do well against. Or an opponent we just enjoy playing.
Once I started playing in chess olympiads, I also found that against certain countries I did well against. On the other hand I suspect there were players who found Papua New Guinea an enjoyable pairing, and not just from recent history.
As mentioned previously I played a tournament in Appletreewick (on the Yorkshire Moors). I was beaten in the qualifying stage by Colm Barry, and again in the final. He mentioned that he had represented Ireland at chess olympiads in the 1980's and a little research turned up the fact that I wasn't the only PNG player he enjoyed beating! Here is a game from the the 1982 Chess Olympiad, where PNG meat Ireland in the second round
Luzern ol (Men) Luzern (2), 31.10.1982