In my own life time, Haiti may be the best example of the failure of traditional mission strategies.  Church after church has poured time and money into Haiti and in 20+ years what has changed?  There are churches everywhere, but poverty and corruption continues to flourish. 

Consider Rwanda, the majority of Hutu and Tutsi people seem to embrace Jesus, but then fall away. Why would 2 supposed evangelical people groups seek to annihilate one another?  Two students in my class at Columbia International University were in Rwanda both before and after the genocide.  When I posed this question to them, they both elaborated how the church came into the community and was readily embraced by the people. Their worship and acts of service were vibrant and impressive.  However, just as the mission workers practiced a separate secular/sacred life style, so did the believers.  Their religion was practiced in the church, at certain times and a place in the home, but faith was never integrated into the daily life and workplace of the believers. Thus, it had little impact on the government and systems of the society at large.
I believe a big part is our failure in working among the unreached, is our ability to help new believers to take their faith into their workplace.  A person’s work is central to his/her life.  The relationships and duties which make up a person’s job, consume them well beyond office hours.  Having a healthy desire to do well at work so as to gain more income is natural.  But unless our Gospel brings transformation into the workplace, I believe we will continue to fail to see significant changes in society.  And unless our cross-cultural workers are modeling the Gospel in the workplace, I fear that Biblical change is not going to take root in the wider community.