Unquestionably, leonardo, always seeking new challenges, had trouble sustaining interest in many of the Florentine art industry's stock-in-trade products – traditional church altarpieces and small Madonnas for domestic display. By the later 1470s, the Verrocchio shop was fast becoming a mere (sculptural) niche player in the “Madonna market.” Remembered today foremost for his mythologies, the Birth of Venus and Primavera (Spring), Botticelli was, by the early 1480s, the dominant madonnero, maker of painted Madonnas, in Florence, employing a large corps of assistants to replicate his designs. Leonardo may have felt some professional jealousy toward Botticelli, whose prosperity stemmed not only from his talents but also from the favor of Piero de’ Medici, who, years earlier, had invited the painter to live with him and his family in the Medici Palace. Rarely does Leonardo mention his very successful contemporary in his writings or reflect Botticelli's works in his own. In fact, Botticelli's Annunciation fresco of 1481, then in the loggia of the church of San Martino alla Scala (now in the Uffizi), is most likely the target of some of Leonardo's harshest criticism: