A simplified three-band model for the cuprates is proposed which reproduces three qualitatively interesting features of the electronic structure of these materials. These are the intense satellite peak observed in the photoemission spectrum, the antiferromagnetic coupling of Cu 3d spins, and the tendency toward localization of doped holes, as evidenced by the broken-symmetry solutions observed in ab initio quantum chemistry calculations in these materials. The first two are well known to derive from the large Coulomb repulsion associated with the Cu 3d orbital; it is shown that the last also follows from this fact. It is furthermore demonstrated that more sophisticated three-band models, when studied in the parameter regime believed to be appropriate to these materials, also exhibit this tendency toward localization. It is stressed that this feature is a consequence of the strong rehybridization and resulting reduction of the kinetic and Coulomb energies, accompanying the introduction of two holes on a single ${\mathrm{CuO}}_{6}$ unit. \textcopyright{} 1996 The American Physical Society.