This study was triggered by a recognition of remarkably low adherence to doctor's or physical therapist's instruction like 40-70% even among people who should be highly motivated. We wanted to understand how that was so. People often blame themselves and other for lack of willpower.
This corresponds nicely with prevalent assumptions in a related field, that of fitness technology, where non-activity is often understood to be lack of motivation, thus the technology will try to create or nurture motivation.
However, speaking with health providers as well as their clients suggests that exercises are often performed wrong, potentially causing more damage than good. This may lead to a yo-yoing effect where the patient will never proceed to a fully functional level and lots of effort is put into repair activity. So we wanted to take a closer look at a population where motivation may be high (want to get well after surgery) but adherence nevertheless comes out low.