It's kind of fun at my age to go back and talk to business-school people. I tell them, "I can summarize everything you need to know to lead a major corporation. Are you prepared to write this down?" And then they get all ready. I tell them I can summarize how I succeed as a leader: Listen to your employees, listen to your customers, shut the f - - up, and do what they tell you.

On my very first day at T-Mobile, I demanded that every time I spoke publicly to the company, all employees across the country would be invited to watch. I faced legal and all that crap, but ultimately we were able to figure it out. We record it, too, so if somebody can't leave the sales floor, they can watch it later. Another thing I did very early on is give every employee stock, which we continue to do. So every time I speak to them I speak way over some of their heads.

I've given my email address to all 3,000 T-Mobile stores. Serious customer escalations come directly to me. Customers get a kick out of me responding to them, and the employees do, too.

T-Mobile is a young, consumer-driven business, and the average age of my customer outside of Bellevue is 27 or 28. They like outspoken, frank discussion. There was an event where it started to come together, I thought the audience would only care about the MLB guys, but they wanted to know what was on my mind. And I literally snapped about the state of the wireless industry. Over the next 24 hours, there was a lot of stuff that was coming out of my mouth that was meant to stay in Vegas, but it hit a chord. It was an action statement for me that I was going to fix this industry.

I visit T-Mobile call centers. We've got about 18 major call centers in the US, and before I was CEO, I heard that no CEO had gone to physically visit them. I go in, they meet me outside, we take selfies as I stand like a piece of furniture, I tell them about how things are going - but most importantly, I say thank you and help them see that their behavior and their work has driven the culture of the company that's changed the industry and the whole world. It's a bit of a love affair.

It's kind of fun at my age to go back and talk to business-school people. I tell them, "I can summarize everything you need to know to lead a major corporation. Are you prepared to write this down?" And then they get all ready. I tell them I can summarize how I succeed as a leader: Listen to your employees, listen to your customers, shut the f - - up, and do what they tell you.

When I used to live in Asia, they used to say, "If you're going to sing karaoke, you want to go after the worst singer." And I'd be coming in Deutsche Telekom after the worst singer.