Additionally, the distribution of d-band centers broadens, as suggested by the increasing standard deviation, indicating the presence of multiple oxygenated species with varying binding strengths, in line with the broad distribution of deletion energies observed in Figure . gives strong evidence for the effects of oxygen content on the thermodynamics of the catalyst at the surface level, which was not entirely clear until now since the descriptor ∆ ḠO is averaged over all oxygen atoms. Secondly, it demonstrates that changes in the descriptor are fundamentally linked to the electronic structure of the platinum skeleton, which evolves with oxygen coverage. This view correlates with the arguments presented in a recent study by Brandes et al., which demonstrated that on polycrystalline platinum, O species influence ORR primarily through electronic effects. Our calculations provide atomic-scale insight into such observations: the progressive shift in d-band center with increasing oxygen coverage directly impacts binding energies of reaction intermediates, deactivating sites, confirming the importance of these effects. Brandes et al. showed that electronic effects dominate over site-blocking under their experimental conditions, though they intentionally avoided higher potentials to prevent formation of stronger oxide species. This suggests that site-blocking is only dominant at very high potential where oxide-species form, as indicated by our deletion energy analysis. This argumentation contrasts with the view that O species block sites mainly via steric arguments, e.g. conventional "site-blocking", and provides a more nuanced picture of the interplay between oxygen species type, electronic structure, and catalyst activity.