According to Vasari, del Sarto had great ability, but lacked ambition. When the king of France invited him to work at his court, full support to paint whatever he wanted, Vasari turned him down and went back Florence. Besides which, he was completely dominated by his wife:
The most excellent painter Andrea del Sarto, more excellent in his life than in his art, was deeply obliged to nature because of a rare talent in painting. If he had devoted himself to a more civil and respectable life and not neglected himself and his neighbors for his craving for a woman who always kept him poor and lowly, he would have stayed in France, where he was summoned by that King [François I] who adored his work and esteemed him greatly, and would have rewarded him on a grand scale. Instead, to satisfy his own appetite and hers, he returned home and always lived in a lowly manner, and was never paid more than poorly for his work, while she, whom he regarded as his only good, finally abandoned him as he lay dying.Portrait of a Young Man, 1517
And although [Andrea’s] assistants put up with the situation in order to learn something in his company, no one, great or small, got away without some malicious word or deed from her.Self Portrait
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