That saying often works in stocks trading. I don’t think we can associate it with gambling in general. The majority of the traders usually be on the wrong side of every trade. That’s how the rich get even richer while the poor get even poorer. It is because the rich have all the tools which enables them to see who owns what. That’s why they almost never make wrong trades. You could even say the game is rigged. It probably happens sometimes in sports betting too but I don’t think it happens as often as it happens in trading.
Sorry....But I can’t quite connect how this relates to trading, or if it does at all, but probably not most of the time. If we use the Bitcoin market as an example, the public sentiment right now is that the market is in a bullish phase, and the price is still rising. However, that doesn’t really connect to sports betting, which is based on individual games or actions.
For instance, if there’s a team on a winning streak and most of their wins are by double digits, and then they have a game where they’re favored by -2.5, the public sentiment is likely to be, “We’ll take that -2.5.” It seems like easy money since they’ve been winning comfortably, but in reality, once the game is over, that team with the -2.5 spread could end up experiencing their first loss.
Bookies know how to trap the public; they set the -2.5 line based on the stats they analyze against the opposing team. However, since the public focuses more on the past successes, they often overlook that the other team is also strong. As a result, the spread gets overvalued due to public sentiment.