In the function docs above that bit of code:
Code:
-- Registration of a callback, handles:
-- self["method"], leads to self["method"](self, ...)
-- self with function ref, leads to functionref(...)
-- "addonId" (instead of self) with function ref, leads to functionref(...)
-- all with an optional arg, which, if present, gets passed as first argument (after self if present)
So this is only executed when you are
registering the callback.