One of the most colourful, and successful characters in recent telco history is on his way out of T-Mobile US.

Few CEOs exit a telco with an enhanced reputation, but such is the success of T-Mobile US under his leadership, John Legere has almost completed an impossible to follow act. Perhaps this could be likened to the retirement of Manchester United Manager Sir Alex Ferguson or US tennis superstar Pete Sampras; how do you follow-up such impressive accomplishments?

Legere’s contract will expire on April 30, 2020, with current COO Mike Sievert taking over as CEO. Legere will remain as a board member of the company, tasked with overseeing the transition of the business as Sprint and T-Mobile US merge into a single entity. His future has not been confirmed just yet, though rumours emerged last week he was being groomed for the top-job at shared-workspace giant WeWork.

“John Legere has had an enormously successful run as CEO,” said Tim Höttges, CEO of parent company Deutsche Telekom.

“As the architect of the Un-carrier strategy and the company’s complete transformation, John has put T-Mobile US in an incredibly strong position. I have the highest respect for his performance as a manager and as a friend, I am very grateful to him for the time together.”

While Legere has formed a reputation as one of the more controversial and colourful characters in the US telco space, he should also be remembered as one of the most successful.

When Legere was appointed as CEO in September 2012, T-Mobile was not in an enviable position. Less than a year earlier, T-Mobile US looked like it would be merged into the AT&T business, only for the Department of Justice to step-in on the grounds of competition. At the end of 2012, T-Mobile US and MetroPCS Communications merged to create a consolidated fourth player with more spectrum, scale and investment potential. In 2013, Legere took control of the company’s fortunes with the launch of the ‘Uncarrier strategy’.

Over a six-year period, Legere’s magenta army have introduced numerous ‘Uncarrier’ offers which have proven to be highly disruptive to the US telco industry. For example, Uncarrier 4.0, known as Get Out of Jail Free Card, saw T-Mobile US pay the Early Termination Fees (ETF) of new subscribers, or Uncarrier 6.0 introduced zero-rating downloads for music streaming.

The result was relevance. T-Mobile US challenged the status quo, creating value for customers which rivals weren’t, eventually forcing the industry to evolve. When Legere was first appointed as CEO, T-Mobile US had roughly 33.3 million subscribers, now it commands 84.18 million. In 2012, revenues stood at $15.9 billion for the 12 months, in 2018, this number increased to $43.3 billion.

What will be interesting to see is whether Sievert can follow-up the wild-eyed persona which Legere has made his own. Sievert is a believer in the Uncarrier strategy, he led the marketing campaigns as CMO prior to his appointment as COO, though Legere was the face of T-Mobile US as well as the mastermind of the grand plan.

For example, looking at the social media presence of Legere, his Twitter account has 6.5 million followers, while a quirky Christmas themed message on YouTube in 2015 was viewed 226,266 times. The energetic CEO even fronted a series of cooking videos under the hashtag #slowcookersunday, the lasted video attracted more than 4.8 million watches on Facebook. Legere is the company’s most valuable brand ambassador, and few can replicate the enthusiasm and genuine belief in the message. What impact this will have on the appeal of the newly-merged business remains to be seen.

The future of the T-Mobile US business is at a pivotal point right now. Once the merger gets rolling it will have to convince Sprint’s current subscriber base to stay as a customer of the newly-merged telco, instead of churning to a rival. Churn is unavoidable in this scenario, therefore it will be a case of damage limitation. Unfortunately, the T-Mobile brand will not be able to rely on one of its most powerful marketing assets before too long.

The T-Mobile loss is a significant gain for WeWork, presuming the rumours are true. Though we would now like to point you to a collection of videos from the combative, colourful and cunning John Legere.