The much slower reaction rates in alkaline electrolytes enable kinetic studies of the HOR/HER via rotating-disk electrode (RDE) measurements. The RDE technique provides a convenient means for correction of mass-transport limitations. During the HER and HOR, molecular hydrogen is produced or consumed at the electrode surface, respectively, and the surface concentration can differ significantly from the bulk concentration, which must be accounted for by applying a mass-transport correction to the measured RDE data. Based on the analytically known solution of the convective-diffusion equation for the RDE setup, the kinetic current, i.e., the current that would be measured if the surface concentration were equal to the bulk concentration, is customarily obtained from the Koutecky-Levich (KL) equation. The kinetic current is the quantity of interest for further analysis and mechanistic interpretation. Thus, there exists a close interrelation between mass-transport correction and kinetic analysis, and the influence of the former must be carefully assessed.