I am mildly obsessed with dabbawallas. Several months ago, I was watching the India special of Top Gear when they described Mumbai’s mind-boggling businessman’s lunch delivery service. They mentioned the dabbawallas’ error rate is 1 in 16 million – in other words, they deliver a meal to the wrong place or fail to deliver in 1 in 16 million deliveries.
This is a better than six sigma accuracy rate in a massive, chaotic city in a developing country for a process with very little automation carried out by often-illiterate laborers. Their process is simple, repeatable, and relies on the knowledge and resourcefulness of the wallas (who have to use shortcuts or less-traveled routes to overcome traffic jams). Their success is a reminder that we don’t have design every process or procedure to the smallest detail to get consistent results, and that we can rely on the judgement and knowledge of non-professional workers.