I went, and my first interview was with René Obermann, who was the CEO of Deutsche Telekom at the time - wonderful guy. And right after hello, I told him that it was my opinion that he could only fail one way in the US. I said, "Do exactly what you're doing - nothing."

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.

We did start with a simple manifesto, as we called it, which was a description of what we were about, and it was the Un-carrier. It was about finding and solving customer pain points in an attempt to fix a stupid, broken, arrogant industry. It was something we felt passionate about. It was our goal to make changes and have the industry make the same ones.

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.

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.

Deutsche Telekom was a brand that people still loved, the nerds loved it, and it was still there, it was still visible. The advertiser was OK. But it was a mess. It was in my mind, though, intuitively obvious what to do. I had some advisers and friends, and we looked at it and said all you have to do is get the iPhone, buy some spectrum, consolidate the industry, reinvigorate the brand, and take this company public.

I went, and my first interview was with René Obermann, who was the CEO of Deutsche Telekom at the time - wonderful guy. And right after hello, I told him that it was my opinion that he could only fail one way in the US. I said, "Do exactly what you're doing - nothing."