More promises don't convince doubters. Better evidence does.

Lenor made a heavy-duty detergent. Nobody knew. And those who did, didn't believe it could compete with the established brands. So instead of telling them, we handed plain white boxes to ten German grandmothers – arguably the world's harshest judges of clean laundry – and left them to it.

No brand name. No scripts. No supervision. Just their own standards.