Summon rates are too low (1%) and banners come too fast and unexpectedly (no event schedule) for F2P players to save up for characters they want to try for, and basically no chance to pity draw because it takes 15 summons at 3000 jewels a pop and you get maybe 1000 jewels a week from login bonuses. You're basically forced to spend money on ingame currency which I refuse to do out of principle. At least they added auto-rematch to cut down on the tedium of grinding that the game expects you to do.