DISH has made it their business model to go after TCV watchers who are not sports fans. However, sports fans seem to be willing to spend more per person for their programming than non-sports fans. Seeing that DIRECTV has a larger subscriber base than DISH, plus the fact that being sports fans they pay more for programming, this would seem to put DISH at a major competitive disadvantage.
Therefore, they need to offer a service that DIRECTV doesn't, and they have failed.
Technology and equipment - yes, this is apparently a DISH selling point, but only to the geek nation, not to the vast majority of TV viewers.
Programming - both services offer more or less the same channels, including HD channels and locals, except for a few variances here and there. No one seems to have a major advantage.
Pricing - After DISH's promotional period ends, pricing for comparable packages is about the same.
Customer service and installation - Both have significant issues here, and no one seems to have an advantage.
So, all things being equal, the message is the differentiator. And unfortunately for DISH, they portray the feeling of a mom-and-pop operation. DIRECTV's messages are polished, professional, much more major league. And that can make a big difference.