http://martinfowler.com/bliki/BimodalIT.html
My second issue is that the bimodal idea is founded on theTradableQualityHypothesis, the idea that quality is something you trade-off for speed. It's a common notion, but a false one. One of the striking things that we learned at ThoughtWorks when we started using agile approaches for rapid feature delivery is that we also saw a dramatic decline in production defects. It's not uncommon to see us go live with an order of magnitude fewer defects than is usual for our clients, even in their systems of record. The key point is that high quality (and low defects) are a crucial enabler for rapid cycle-time. By not paying attention to quality, people following a bimodal approach will actually end up slowing down their pace of innovation in their "systems of engagement"
