The presence of stars on retrograde orbits in disc galaxies is usuallyattributed to accretion events, both via direct accretion, as well as throughthe heating of the disc stars. Recent studies have shown that retrograde orbitscan also be produced via scattering by dense clumps, which are often present inthe early stages of a galaxy's evolution. However, so far it has been unclearwhether other internally-driven mechanisms, such as bars, are also capable ofdriving retrograde motion. Therefore, in this paper, we investigate theefficiencies with which bars and clumps produce retrograde orbits in discgalaxies. We do this by comparing the retrograde fractions and the spatialdistributions of the retrograde populations in four $N$-body$+$smooth particlehydrodynamics (SPH) simulations of isolated disc galaxies spanning a range ofevolutionary behaviours. We find that both bars and clumps are capable ofgenerating significant retrograde populations of order $\sim 10\%$ of allstars. We also find that while clump-driven retrograde stars may be found atlarge galactocentric radii, bar-driven retrograde stars remain in the vicinityof the bar, even if the bar dissolves. Consequently, we find that retrogradestars in the Solar Neighbourhood in the clumpy models are exclusivelyclump-driven, but this is a trace population, constituting $0.01-0.04\%$ of thetotal stellar population in this region. Finally, we find that neither bars(including dissolving ones) nor clumps in the models are able to producerotationally supported counter-rotating discs.