Originally Posted by aimetti
My guess is due to the company position. Att needs the gs4 more than Samsung needing Att. They make billions anyways. Htc however is in search of some real profits and phone sales. Just bargaining positions.
That's likely exactly the case. Samsung is doing amazingly well with their smartphones, and are by far the leading seller of Android phones, with the Galaxy S series in particular being wildly popular. So as you say, AT&T needs them more than vice versa.
Such is not the case with HTC, who has been really struggling financially for some time now. HTC needs to be able to sell their flagship on AT&T, or their chances of surviving (at least in the US market) are going to dwindle.
For all we know, AT&T even compensates HTC monetarily to keep the bootloader locked. Something HTC isn't in a financial position to refuse (and again, not the case for Samsung).
Its really a shame, as I think many of us can agree that HTC by far makes the better hardware, compared to Sammy's cheap looking/feeling plasticky devices. Really unfortunate that such a beautiful device may be marred with an unlockable bootloader.