Do current bad decisions (Monthly EQ, Nerf, Sales etc.) and wrong direction (no more focus on free to play, no new idea except bullsh*t event like Dimensional Arcade, Fantastic force recruitment, mid champ sale "Solvarch") lead to drastic decline in revenue? (Even when they sell more than before)
If they keep testing "new ideas"/nerfing decent champs without thorough consideration (or suitable compensation), the end of their era will come at the soonest. Anyway, 10 years for a game is also very good already.