Vasari 's Life of Perugino defines Perugino's reputation in a way which became conventional into the nineteenth century and beyond. It is this conventional view which Reynolds followed and Ruskin seeks to challenge (see Reynolds on Perugino and Ruskin on Perugino).
For Vasari, Perugino, as the master of Raphael, provides a link between the second stage in the development of Italian art (the stage which added regola/rule, ordine/order, misura/proportion, disegno/design/draughtsmanship/understanding of form, and maniera/manner/making figures of the greatest possible beauty), and the 'perfezione' of the third stage, the age of Leonardo da Vinci, Raphael, and Michelangelo. Vasari recognises the strengths of Perugino; many artisans came from France, Spain, and Germany, and other countries, to learn from him the grace with which he used colours. Moreover, many people traded in his paintings until the appearance of Michelangelo and the perfection which he brought to the arts ( Vasari, Le Vite, Testo III.614).
Vasari reported complaints that Perugino often placed the same details in many pictures, and often made all his figures with the same expression. Vasari suggested that this was the result of Perugino's greed in taking on too many commissions. Perugino answered the charge of repetition by saying that that people had liked the figures when he put them in his earlier paintings, and he could not do anything about the fact that they had changed their minds ( Vasari, Le Vite, Testo III.611). Implicit here is perhaps a cultural shift away from medieval notions of a workshop making functional objects for religious contemplation.