Why is it that a mesh parented to a bone remains in pose position while the armature is in rest position?

so like I said in my title, when I parent a mesh to a bone, then I pose the bone, then set the armature back to rest position, the mesh doesnt actually move with it?

I first learned to do armature stuff by linking to vertex groups instead of parenting, and that allows the mesh to follow the bone into rest position, is that something that just doesnt work with bone parenting?