TFA abbreviates the quote from T-Mobile CEO John Legere. Here it is in full:
"Marketing thought we could call it 'unlimited', because that would sell. But then engineering pointed out that our network couldn't support that kind of load. So we had legal work out deals with the handset manufacturers so that the phone would limit data usage anyway. That way, we could call it 'unlimited', but in reality, it would be limited; Clever eh? But our customers noticed, and are downloading apps that hide their tether usage, rooting their phones, writing code to mask their activity, etc. It's all their fault. I mean, obviously we have the right to lie to our customers, and put whatever software we want on their phones. But now they are changing that software! They are thieves I tell you. THIEVES!"