"RESET"

I don't quite understand the need for "reset" buttons on products.
That function is always available by cycling power -- even for devices
where that is difficult for the user (e.g., PoE, BBU, etc.)
Shouldn't a device be able to get itself out of a "pickle" without
requiring the user to intervene?  Particularly devices that are
intended to "run forever"?
I.e., it seems like the presence of a reset button is a tacit admission
that the engineering is "lacking"...