Of course there is not a certain answer why to choose satellite based TV services over the other cable and emerging fiber optic solutions. However, we will give it a best shot to highlight what advantages Dish Network has to offer.
First of all, Dish Network provides the TV service using the satellite signals, just like the GPS systems we have in our cars to find our location. The broadcast is received using the dish antenna direct from the satellite. That's why the broadcast is available almost at any location. This is the first advantage.
Second, the broadcast type is 100 % digital. So even the minimum level of quality is very good. How? I'll explain them later in this article.
Third, if you need to relocate, then you can carry your equipment and be able to watch channels exclusive to Dish Network at your new place.
The good thing about using satellite receivers is that there is a wide variety of channels available. This means that while we can watch only about 90 channels using cable TV service, we can watch more than 300 channels by subscribing to Dish Network or other satellite TV providers. There are international channels available as well!.. 
Similarly, pay per view movies and events are limited to around 40 for a cable TV service but Dish Network has approximately 80 pay per view channels available.
The packages at Dish Network 
starts from $19.99. Have you heard about such a price from Time Warner or Verizon??
I kept the best thing about Dish Network to the end, which is... NBA League Pass to watch all NBA games, NHL on the Ice to watch all hockey games and ESPN Gameday to watch all College Football and Basketball games. Good deal for the fans!
About the 100% digital channels: Now, a lot of the air channels and cable channels are based on analog broadcast. However, by February 2009, just 10 months from now, there will be no more analog broadcasting and all channels will be digital (by federal law). The problem is that not everybody has digital TV sets yet. Since previous televisions that we've used are not compatible with the digital broadcasting we will need to buy new TVs and spend a lot of extra money. For those who want to keep their existing TVs, there is a cheaper solution around this, which is to buy a small digital to analog converter to use with their existing televisions. However if you already have or if you order Dish Network service then you won't have to buy a new TV or buy any equipment. You won't have to think about this transition if you have Dish Network. Basically, there are two quality levels for digital broadcasting. One is SD (Standard Definition) and the second one is HD (High Definition). Of these, SD has the minimum quality, but even this minimum quality provides great picture and great digital sound.
Last couple of Dish Network offerings is that they are now doing FREE Installation as early as 24 hours, providing FREE DVR (Digital Video Recorder) upgrade so that you may record your favorite TV shows and playback again. Also you are eligible for a FREE HDTV upgrade to watch High-Definition channels and FREE Home Theater System or airline ticket (a $100 value). And... You don't want to say "NO" for a 3 months of FREE service , do you?! (limited time offer).
Even cable or other TV providers might have their own advantages but I've tried to highlight the advantages of subscribing to Dish Network in this article. Please share the best things you like about your current TV provider in the Comments section. Thank you!
You may find the Dish Network Specials here.