We have been conducting a longitudinal study of two cohorts of teachers since they began teaching, 20 (originally 22) in 2004 and 20 (originally 23) in 2007. Over the period reported here -- to mid-2014 -- nearly all the teachers stayed in teaching and most maintained quite a high level of motivation. Although they faced many challenges, they also found many sources of satisfaction and devised strategies to deal with the challenges. Several of the more difficult challenges arose from school system policies and initiatives. We concluded that (i) decline in motivation over the first decade of teaching is not inevitable; (ii) teacher motivation deserves more attention than it has typically received; (iii) teacher motivation needs to be considered in the context of a more adequate general theory of education; and (iv) policy developers and system administrators should consider the negative impact of many top-down mandates and interventions on teacher motivation, and instead work in dialogue with teachers.