We focus on a simple -yet powerful -Hückel model to illustrate this point, which we confirm with density functional theory (DFT) calculations. Sometimes, the single-electron picture might not be enough. In those cases, we show how the many-electron picture provided by standard excited state calculations should be employed to rationalize photocyclization feasibility in DTE photoswitches. In Scheme 2 we depict the two elements defining our strategy for the rational design of molecular photoswitches transforming between open and closed forms: (i) orbital localization and (ii) orbital (pseudo)symmetry. The main conclusion of our investigation is that both elements are necessary ingredients to obtain electrocyclization-based photoswitchable dyes. We provide rules of thumb based on these two categories and demonstrate the predictive power of our approach by applying it to examples from the literature.