MOOCs for learning the basics of programming have become popular among people with a diverse range of backgrounds, interests and learning contexts. Studies show that learners who enrol in MOOCs tend to have different motivation from learners in traditional courses, but it is not known how motivation differs for people with different backgrounds. This study aims to describe how the motivational factors behind enrolment in programming MOOCs relate to learners' characteristics. The data were gathered in the spring of 2017 with a motivation scale (FIEM) from 1,536 participants of the MOOC 'About Programming'. Using comparative analysis, differences in motivational factors between groups by gender, employment status and previous experiences in programming were found. Correlational analysis revealed that educational level, age and self-evaluated probability of completing the MOOC were also related to motivational factors. Different people are motivated by different factors, indicating that this knowledge could be used to design interesting and motivating programming MOOCs, which are relevant to learners with various backgrounds.