Ailments are various negative effects that can be inflicted on a character.
They are inflicted in various forms, but first they provide an ailment accumulation value, which if exceeded by the enemy's resistance limit, causes the ailment to occur, and then the effect lasts for 10 turns.
The higher the ailment resistance value, the harder it is for the ailment to occur.
Since the ailment accumulation value decays slightly each turn, the ailment must be inflicted within a short period of time in order to occur.