Through a historical review, this text analyzes how the Hotel Posada del Sol in Mexico City, characterized by two convergent modalities of failure, constitutes testimony to an era: as a sui generis hotel typology without success and as an inadequate headquarters for public institutions neglected due to lack of state commitment. This analysis brings visibility to both a scarcely documented and abandoned heritage building, as well as a significant public institution in housing policy that has been historiographically relegated. Furthermore, it examines the problematic nature of ornamental modern architectural heritage, susceptible to erroneous characterizations and social appropriations that configure what we call popular heritage.