Under 2.5 bet is just the opposite. You will win this bet in case the game ends with zero, 1 or 2 goals. Anything more than 2 goals in the match and you lose a bet. The winning results need to be 1-1, 1-0 or even 2-0 for you to win the bet.
Both are very simple markets but they demand a bit different preparation and research. Unlike the winner of the match, prediction for this market will demand following more details. For example, you want to follow the scores in the leagues to learn which are consistently low-scoring or high-scoring. It's also useful to pay attention to coaches and their strategy and how they act against defensive and aggressive-playing teams.
There are few good reasons and the first one is that it's very popular. It is less risky than over 3.5 goals, so there are a lot more predictions available online and many more resources to compare tips and consider what could make a winning ticket.
Another advantage is that this is the perfect market for when bettors are uncertain in the outcome of the game. A match between two high-scoring teams could be a perfect start for betting on this market.
The last reason to bet on this market is pretty good odds. This market usually gives a nice balance between security and a lucrative cash flow. Certainly, it doesn't have odds as good as high-risk bets but it's a pretty good compromise considering it's a rather safe bet.
Under 2.5 prediction is like a middle ground for all over/under markets, as two goals are the most common occurrence, while 0 goals is also a good possibility. It is the most conservative estimate of any fixture but also most reliable so in case it offers good odds, it's worth taking the opportunity.
Besides players and leagues, you want to follow managers and their work as that will tell you a lot about their strategy and style of play. If they play aggressive instead of defensive, it could make all the difference. After all, they are directing their squad towards victory or failure, which will later recognize the more you follow it.
Still, it's not recommended to use that all the time as you won't get back all you invested. Not only that but as the match comes closer to the ending, the amount you get back gets smaller. Of course, when the match is concluded and few minutes prior (depending on the bookmaker) is not possible to use this feature. Read the terms and conditions for Cashout bets before you just jump into it.