haphazard

“Do not make such haphazard changes to the settings; instead, adjust the knobs carefully, a bit at a time.”

“The haphazard efforts of a few, working here and there without concert, easily spent themselves in attaining results far short of what were needed.”

“"[...] I suspect that it mostly happens haphazard, though afterwards various noble reasons are invented. About marriage I am cynical.””

“You should never talk about your own fingers, and haphazards, to genteel people. You should only talk about agreeable subjects as I do.”

“I consulted my mother, who was punctiliousness itself, and decided I must go Monday, as agreed. I should be with her again on Wednesday. On such haphazards hang men's destinies sometimes.”