Purpose of restoration is to ensure sustenance in the future. It helps in maintaining the original structure. It essentially transcends the aesthetics and historical significance into the future. Efforts should be taken to warrant that the original design, material used for these primal restorations should ensure that primary values that are manifested in the building architecture are preserved. Brandi stressed for minimal intrusion while divulging a schema. Brandi Theory focuses primarily on maintenance of the original aesthetical values and heritage of a building. The criticism for Brandi theory was that there was importance given only to the aesthetic of the past. Contemporary trends in modern architecture were not given any importance by Brandi. He essentially considered architecture to be a work of art. He did not factor in the nuances of modern art. John Ruskin was an ardent critic of the ideologies proposed by Viollet-le-Duc. Viollet-le-Duc incorporated his own themes and ideologies in the restorative process of heritage buildings. Reason cited by Viollet-le-Duc was by incorporating ideas that the present ideologies would be reflected in the bundling. In this book Seven Lamps of Architecture, he speaks extensively about the Gothic revival and the beauty of the historic architecture. He essentially states that the beauty of building is not in the ornamentation or value of the land rather it is in the beauty of age.
Ruskin stated that the original beauty of architecture would be lost in the process of revival. In extension to this theory William Morris also proposed an extension of this ideology. It was proposed in the name of restoration the original value and the intrinsic culture of the past will be lost. This leads to the original value of the building being lost in the process. Each restoration causes the value of the building to be subtracted. Criticism to the theories of Morris and Brandi is that no modernity or innovation will develop in this process. By adding only elements of the past there is a problem of not expressing the current modernity notions into the building design. This could create a void and have not many mediums to present the current modern architecture. In any event of restoration there should be reconciliation between the past and the present. It is not suggested to completely abandon the older aesthetics but modernity should be encompassed for functionality and to represent the current architectural trends of the people. Thinning out theory by Giovanni suggests that it is best to incorporate older themes with newer materials. This would ensure sustenance and extends the ideology of the past to the future generations. Nuances and intricate details of the theory, importance of fire safety and maintaining architectural integrity have been probed in detail in the following.