It really has very little to do with poor network capacity planning, I think the reason the caps are being put in place is specifically for network capacity planning.

Cellular data usage is expected to double every year for some time. Imagine carriers doubling their capacity and doubling their network expenditures every year while revenue is only increasing at 2% - 7%. That's not a business model that's going to work.

It would be very difficult to keep up with the exponential growth and at the same time be profitable if all customers had cart blanche data plans.

Having a cap causes people to change their behavior. They use their data more efficiently: they add wifi networks, they adjust their app settings to make the plans work.

Think about the number of sprint users vs. the number of AT&T users who have set up wifi networks on their smartphones. Companies who only offer unlimited don't give people any incentive to be efficient with their data.

Everyone will change to tiered, don't fool yourself into thinking otherwise, Sprint included, no matter what Dan Hesse says. Sprint isn't going to absorb all the highest data users and deal with 200% or 300% data growth per year just to be the lone wolf with an unlimited offering. Best case scenario they'll have 1 or 2 tiers available and have a big upcharge for unlimited service.