  We consider the superconductor-semiconductor nanowire hybrid Majorana
platform ("Majorana nanowire") in the presence of a deterministic spatially
slowly varying inhomogeneous chemical potential and a random spatial quenched
potential disorder, both of which are known to produce non-topological
almost-zero energy modes mimicking the theoretically predicted topological
Majorana zero modes. We study the crossover among these mechanisms by
calculating the tunnel conductance while varying the relative strength between
inhomogeneous potential and random disorder in a controlled manner. We find
that the entire crossover region manifests abundant trivial zero modes, many of
which showing the apparent `quantization' of the zero-bias conductance peak at
$ 2e^2/h $, with occasional disorder-dominated peaks exceeding $ 2e^2/h $. We
present animations of the simulated crossover behavior, and discuss
experimental implications. Our results, when compared qualitatively with
existing Majorana nanowire experimental results, indicate the dominant role of
random disorder in the experiments.
