Appendix: POISONED: A poisoned creature has disadvantage on attack rolls and ability checks.
Would this condition ever be applied to a creature that's stung by giant scorpion's tail-sting attack, or bitten by a poisonous snake (both found in the Monster Manual), or shot with a poisoned arrow? I can see several instances where poison damage is applied to a creature, but very few where the poisoned condition is applied (so far just the magical poison dagger).
Even poison you can purchase only inflicts poison damage and makes no mention of applying the poisoned condition. There seem to be a great many anti-poison measures but little to no poisoning methods.