Patrick, to clarify: market demand is the most important leg for supply chain improvements to happen, because it is the modern retailers who have the weight to provide momentum for the big and urgent changes.
The demand generators (the retailers) need to proactively pull up the supply chain, instead of only focussing on creating demand and waiting for improvements to bubble up from suppliers. Most retailers and brands seem to be only focussed on encouraging consumption, as a panacea for all problems (GDP growth, poverty alleviation et al). My point is that this single-minded focus leads to a blinkered approach that ignores much bigger issues. Modern retailers and brands cannot afford to ignore those issues.