There is a saying in business “if you want a successful business start with the customer and work backwards”. This should equally apply to development as it does to business. Over the last two decades there have been too many good intentioned NGOs and organisation in developing world that have wasted thousands of man hours and millions of dollars on projects and applied technologies that have failed to improve the situation; in many cases it made things worse.
Projects mostly fail for the same reasons, they simply did not fully understand the cultural needs by failing to ask what was needed. Many project fail becuase planners  make too many assumptions in the early planning stages, and resist change to the planed technological fixes that they assumed would solve the problem .
No matter how good the technology, if it is not appropriate the project will fail. This may seem a basic error but you would be surprised how often project planners fail to undertake a participatory assessment before planning starts.
The general rule should be not matter what technology you have to offer no matter how good it is or you think it is and not matter how much benefits you assume it may have on poverty reduction and a better life for the people you are trying to help: before you start planning and installing inappropriate technologies; STOP and ASK, not your partner or the guy next door.. ask the people you want to help a simple question . What is it that you want us to help you with, what do you need to make your life immediately better. It is worth bearing this in mind before with all good intentions venturing into the unknown bringing shiny new technologies to poor people who can’t manage it or simply don’t want or need.