Snail and slug culprits typically leave some sort of latticework behind, like on this hosta pictured below.
Which can also resemble damage from leaf eating beetles (of which there are many)..
Which can also resemble the work of caterpillars.
One can often id the specific insect or caterpillar doing the damage by the pattern they've left behind, esp whether they have generally eaten from leaf edges (for example, grasshoppers and crickets do this) or from the center of the leaves.
To do this though you really need to have the pest id narrowed down since as you can see from the examples, damage patterns vary.
However if there are no lattice patterns and the entire leaves are gone - including the leaf stems - you likely have something larger causing the problem, like a small mammal.
If it's rabbits, you should be able to spot some pellet droppings near your plants.
If you could post a couple pics, might be able to narrow it down for you.