I wonder how people can play 15 seasons?

[Maxtax]

I guess, they like the game and try to ignore the everyday annoyances?

Above around L25 its getting more challenging and you are starting to be more fanatic because you are meeting full leagues with very active managers. At those levels managers are focusing to their opponents more because everyone has met each other for sometimes and to their teams and players without changing them to often, its more often to see someone to add roles and SA. It doesn't seems to me that annoyance is present judjing from the fact that most ppl taking good care of their teams. I cant say that ther are often big surprices to results.