From my experience, those "killers" come from 1) teacher, 2) student, 3) school.
Teachers play an important role in education since teachers are the one who teach/transfer knowledge to students and help students avoiding making mistakes from experience. Belief of teachers is the most challenge. If teachers don’t want to carry out something new, it is no way to let students get something new. It may appear amount some “success-teachers”. They are the teachers whose students are getting good results in school/public examination. The success-teachers sometimes think it is useful using their original teaching style, why bother changing it into something they do not be so familiar? It may be the first reason. The other reason is that the success-teachers face lots of pressure from the parents/schools. Schools/parents expect student to get an excellent result; if the teachers adopt innovation in their teaching (that means they have to change their styles), students’ good result can’t be quarantined. So teachers may not be willing to take such risk that they may lose their job.
Students may also face similar problem like teachers, especially secondary/universities students. They have already developed their own learning styles and some may not really want to change their habits. Besides, students usually focus on homework (workload). For example, in blended learning, students are encouraged to discuss on internet forum and to share anything related to the courses. Actually it is good for students to learn much more, but, in fact, they may not agree that. They may feel uncomfortable because it is an endless homework for them.
School culture also affects the trend of education. I have met a situation. There are two schools which cultures are totally different. In school A, the principal is very interested in using new technologies but the school teachers are very reluctant to that. In school B, the teachers are happy to change but the principal do not believe that it is not necessary to have innovation in the school. In both cases, innovation cannot be carried out.
Zachary