In the context of multistep reactions, one step is commonly referred to as the rate-determining step (rds): This step typically exhibits the highest activation barrier, becomes the limiting factor for the overall rate, and its stoichiometric coefficients yield the observed reaction order of the concerned reactants/products. However, from the Butler-Volmer model, the activation barriers are varied through the electrode potential, and the step with the highest activation barrier may change upon changing the electrode potential. Similarly, local changes in reactant activities may cause a shift in which step is rds over the course of a potential scan. Only when the potential window is sufficiently limited and the activation barriers sufficiently different, the same step may be expected to remain rate-determining. The term rds can, therefore, be misleading, and we introduce the concepts of the smallest-rate-constant (src) step and the high-rate-constant (hrc) steps instead. If a src step exists, any other step is, per definition, a hrc step. The identification of the src step is most useful in the analysis of a microkinetic model as it allows the simplification of its equations following Eq 10a (𝑠 and 𝑡 could be any multiplicands). Such a simplification is often necessary to solve a model analytically, but it must be applied carefully: The multiplicands must not compensate for the difference in the value of the rate constants (Eq. 10b), a fact that can limit the applicable potential range when the multiplicands are a function of potential, or reactant activities. In such case, the intermediate coverages of hrc steps can be approximated by Eq. 10c, as if these steps would be in quasi-equilibrium.