I stopped going after an initial probability/stats tutoring session, as a FE student in the 1980s . I think I reasoned away (to myself) the promised help, thinking that I had a lot of work to cover generally and that the specific help was going to be too time consuming - what they now call, I think, 'an opportunity cost'. On reflection, there was a bit of an issue with the tutor's pedagogy, in that I lacked much upbeat feeling for the joint enterprise that was being offered towards the subject - perhaps if I had been more personally engaged in the recruitment that could've been different, I suspect I lacked that 'being tutored' sensibility and my mother finding ad hoc a tutor was symptomatic of that. As a part-time tutor myself I have had a single session only student and some early leavers. They are usually interpreted to be affective filtering, in part in response to my session content/delivery.