The Latin root of desultory means "of a circus reader who leaps from horse to horse" - which sounds wonderful in a way, but which carries connotations of being trapped on a merry-go-round. Dr. Johnson wrote of his friend "Sober" that "[his] art is, to fill the day with petty business, to have always something in hand which may raise curiosity, but not solicitude, and keep the mind in a state of action, but not of labor." Steadfastness is not necessarily a virtue, and changeability need not always be erratic, but this seems an exhausting form of idleness! See: CAPRICIOUS, DISTRACTED, DRIFTER, FLÂNEUR, FLIGHTY.