This paper discusses a complex issue: why teacher education input and interventions have limited or no impact in the classrooms. It discusses some practical examples and issues and their implications for teachers' learning and motivation to develop teaching. Analysis of the findings suggests that as teachers re-entered the reality of the school situation after taking a teacher education course, they did not continue to sustain the process of their learning or improvement and easily succumbed to the dominating culture of their schools. In other words, in-service education projects falter at the implementation stage. The paper raises some important issues relevant to mathematics teacher education to illustrate conditions and challenges for successful implementation in Pakistan. It is expected that this discussion will stimulate teacher educators in Pakistan and at large to reflect on their own ways of working with teachers, and to challenge the assumptions that inform and shape their theoretical perspectives and practices.