Don’t fight culture (If people cook by stirring their stews, they’re not going to use a solar oven, no matter what you do to market it. Make them a better stove instead.)
This is incredibly sublime and extremely important. To some, helping means imposing their points of view onto those being helped. This sometimes works intra-culture, usually it doesn't work at all.
The example given on stirring stews versus solar ovens is a trivial one but it is a starting point to understanding the nuances involved. Don't fight it. Fighting it means you're going against the collective knowledge of those you are trying to help. This can be as difficult as trying to change their DNA.