If Marks and Spencer line of socks stops selling they don’t blame the punter. So when social innovation doesn’t engage people, why is it that the intended recipients are often viewed as the problem, not the social innovation.

The trick is thinking about pull, and trying to forget the public system instinct to push.

One of the Gates Foundation innovations was Chlorhexidine, an antiseptic that, in some contexts, is a lifesaver if spread on the umbilical cord at birth. But the Foundation couldn’t get people to use it.

In one of the Indian test sites, the research showed that people put Gentian Violet on the umbilical cord. Gentian Violet has many antibacterial qualities, but it doesn’t save babies lives.

So we have something that saves lives that people won’t use. And we have something that people will use that doesn’t save lives. What to do?

Put some violet die into the Chlorhexidine. This way we are true to the core -the thing that makes it work, the antiseptic- and we are true to the adaptable -the thing that makes it sell -the colour violet.