In boxing, rounds are scored individually. The fighter who wins the round (typically by landing more punches, altho there are other factors also) scores 10 pts. The other boxer typically scores 9 pts, unless he was soundly beaten in that round in which case they may score it 10-8.
What this method does is keeps fights close. A boxer can get his a** kicked all over the ring for 3 minutes -- the punch count could be 40-0 -- and he's only down two points. The next round he ekes out a slight advantage and he's back within a point in the match.
IOW, you could outbox me for 6 of the rounds of a 12-round fight; for the other 6 rounds we're more or less even , but I end each of those rounds with a flurry that leaves the judges with the impression that I won that round. At the end of 12 rounds, the scorecards could be even.
What it really means is that it would be really easy for judges to manipulate the outcome of boxing matches. Luckily, judges are always 100% honest, so even though millions of dollars are bet on boxing, nothing shady ever happens. But I'm just saying that it *could*.