  We investigate the effect of random defect scattering on the orbital Hall
effect by solving a quantum Boltzmann equation. Depending on the specific
orbital textures, diffuse scattering by an \emph{arbitrarily} weak disorder can
affect and even fully suppress an intrinsic orbital Hall current. From the
results for a simple model, we infer that disorder can play an important role
in orbitronics in general.
