And there can be many problems causing that, none of which meaning the Earth is really flat. Edit** misspelled word**
First question, is it storming there?
Second question, how often does your signal go out?
Third question, when was it installed and was it installed professionally?
Fourth question, are there any obstructions in the way like trees?
Fifth question, have you looked at the wiring outside at the dish and is there any visible damage?
Sixth question, have you called and complained about this?
Take it from one that was a reputable installer, if it was installed properly, you should get around a 99% signal on a clear day and only lose signal for a few minutes during the hardest rain.
If you know how to go to your signal meter on the box, do so on a clear day when it is working, for DirecTV the signal is in percentages, if it is not in the very high 90s then there is a problem. If it is dish network, they use a different scale but if it is not in the high 70 to 80s then there is a problem. Your dish could be out of alignment, you could have corroded wire connections, or you could in fact have a power issue in the house causing power to dump to ground. Your system should be grounded, and it can also go through the box to ground. There are several problems that can arise that cause it to go out. 99% of them can be corrected by a trained installer. That last 1% being things that are out of their control like a tree that has grown into the way. If there is nowhere else to move it, then they will not be able to fix it without the tree being trimmed or removed. I have seen quite a few "issues" with bad installs, customers screwing with the dish, and house electrical problems.