So the guy with higest Average Quality has made the league, he had some friends that were invited it, they had other friends that are probabbly you'r mutual friends so you got in that league.
There is an easy way to make ur league easier for next season as there's a way to make it hella hard
If you start adding teams that are on 6th-7th position with lower Q than yours, by the end of the season(just check thoes teams that were in CL and their standings to pick the right people) anyhow if you managed to add more than 13 guys and you've got the higest Q im pretty sure that you'll be the one leading the league with all your friends that you recentlly added in.
A way to make it harder, keep an eye on all different competitions, first days transfer market & browser ur CL opponents leagues to pick the guys with higest Quality around^^ This way you'll most likely get a hell draw league next season