Referral marketing is one of the most successful techniques that companies can employ to ensure they stay on top of their market. And many iconic companies like Uber, Airbnb, Dropbox and Netflix, owe much of their incredible initial growth to supercharging natural word of mouth with a referral program. But a mistake that we think many of these titans have made, is in not realising that no brand is too big for referral marketing and, once they have become established household names, they have often failed to update and upgrade their referral program to support the continued growth of their business.