A basic point I feel I have not pondered enough is that people who are financially cornered may borrow unwisely---at least sometimes. A Microfinance Insightsarticle by Lilian Simbaqueba and Vitalie Bumacov of the Colombian credit-scoring company LiSim made me think of this now:
Sendhil Mullainathan, the second MacArthur Fellow here blogged, writes in Seed Magazine about how human psychological foibles influence how we borrow and save: