First of all, all games between teams must be played, even if the two teams win or lose. The ranking is based on the following.
1, the number of wins (note that it is between teams, different from athletes);
2. If there are two teams with the same number of wins, they will be sorted according to the winning and losing relationship;
3. If three or more teams have the same number of wins, they will be ranked according to the number of wins of small nets (determined by the winning or losing relationship of several pairs of athletes in each game);
4. If according to Article 3, between teams with the same number of net wins: if there are two teams, they will be ranked according to the winning-losing relationship; If there are three or more teams, rank them according to the number of net wins;
5. According to Article 4, if the number of net wins is still the same, if there are two teams, they will be ranked according to the winning or losing relationship; If there are three or more teams, they will be ranked according to the net winning score;
6. If according to Article 5, between teams with the same net score: if there are two teams, they will be ranked according to the winning or losing relationship; If there are three or more teams, the order will be decided by drawing lots.
It's so complicated, but in practice, there are usually about 4 teams in each group, and the chances of the last few are extremely small. I hope you can understand.