Differences between singlet and triplet states can be understood by considering the different contributing energy terms. Singlet and triplet states are both affected by an attractive Coulomb interaction favouring locally excited states while singlets are also affected by a repulsive exchange interaction favouring CT states. The discussion for triplet energies is a bit more ambiguous and depends on the reference chosen. If one considers the Kohn-Sham orbital energies as reference, then one finds that triplets are independent of any exchange contribution. However, if one further considers that the LUMO energy is lowered by the exchange interaction between HOMO and LUMO, then one finds that triplet energies are indeed stabilised by this exchange interaction. Independently of this discussion one finds that low-energy triplets should be more localised, which is well represented by the data shown. Furthermore, the above plots highlight the differences between singlet and triplet states, which cannot be explained by simply reordering the states without also mixing them. Clearly, there is no one-to-one correspondence between the singlet and triplet states. These differences are important for at least three reasons. First, it should be understood that the photophysics of these molecules cannot be understood in terms of a simplified picture containing only two or three MOs but that a number of terms ultimately influence the final energies of the states. In this context, it has been pointed out, before, that the idealised picture where singlets and triplets differ by twice the exchange energy would only hold if their wavefunctions were the same except for the spin coupling. Discussions of how to go beyond this and understand singlet-triplet gaps within and beyond the orbital picture are provided in Refs 7,28. Second, the discussion shows that the available space for molecular design is larger than one would anticipate viewing only two or three MOs. Indeed, there are a large number of terms that can potentially be fine-tuned to optimise the overall photophysics. Third, differences in the wavefunctions of singlet and triplet states explain why singlets and triplets differ strongly in their computational description using, e.g., TDDFT or the Bethe-Salpeter equation. Being aware of these differences may help in the development of computational methods that provide a balanced and accurate description of singlets and triplets.