Jefferson once said, "My first wish is that the labourers may be well treated". Jefferson did not work his slaves on Sundays and Christmas and he allowed them more personal time during the winter months. Some scholars doubt Jefferson's benevolence, however, noting cases of excessive slave whippings in his absence. His nail factory was staffed only by enslaved children. Many of the enslaved boys became tradesmen. Burwell Colbert, who started his working life as a child in Monticello's Nailery, was later promoted to the supervisory position of butler.Wiencek, 2012, p. 93.</ref>