According to published reviews and other contemporary accounts, Jenkins's acknowledged proficiency at the piano did not translate well to her singing. She is described as having great difficulty with such basic vocal skills as pitch, rhythm, and sustaining notes and phrases. In recordings, her accompanist Cosmé McMoon can be heard making adjustments to compensate for her constant tempo variations and rhythmic mistakes, but there was little he could do to conceal her inaccurate intonation. She was consistently flat, sometimes considerably so. Her diction was similarly substandard, particularly with foreign-language lyrics.