Guaranteeing a minimum price also means there is no incentive to improve quality, grumble coffee-drinkers, who find that the quality of Fairtrade brews varies widely.

• 保证最低价就意味着没有提高产品质量的动力了，饮用咖啡的人埋怨说，他们发现公平贸易下的产品质量相当参差不起。