innovation

Poor vision may not seem like an economic problem at first glance.

Flood irrigation: that's how poor farmers in developing countries usually water their crops. It's wasteful and too water-intensive to work in the dry season, but until recently there haven't been other viable options — a traditional drip irrigation system could cost thousands of dollars.

Here's some conventional marketing wisdom: People who live on less than $2 per day simply aren't a worthwhile target demographic.