If you ever have to hand off a scene to another artist with maybe less familiarity in Maya and you want to make sure certain objects are locked off and cannot be deleted, sometimes its not enough to hide them, asset them, type in huge bold letters DONT DELETE!!!! or whatever your flavor. Instead, select your object and run this little python script to lock your object from being deleted-
import maya.cmds as cmds
selection = cmds.ls(sl=True)
cmds.lockNode(selection)
To unlock your object, use the lock = false command-
import maya.cmds as cmds
selection = cmds.ls(sl=True)
cmds.lockNode(selection, lock=False)
This does not prevent attributes in the channel box from being edited, but you can run a simple hide and lock on any parameters you don't want altered