Autobuff

In Ragnarok all consumables share the same delay, using a buff item (e.g. Speed Potion) will prevent you from using any other consumable, even potions. If this happens while your HP is dropping then you might end up dying.

You don't have to worry about this with Lemon Tools, the Autobuff and Autopot are designed to work together, keeping your buffs active, without making you die.