I have said this before and I will say it again. Your story dictates the voice you take. It will also dictate whether or not you should be writing in first person or third person. What I see, however, is that far too many authors seem to take the wrong approach for their story, and in the end, the story is really lacking.
I personally believe a lot of people take the first person approach because of the ease in writing it. In other words, if you just put yourself into the mind of the character, you just tell us what you are doing and experiencing. As a writer, if I take this approach, I just listen to the words flow out of my head and tell you what I am thinking, if if I am a vampire or a zombie at that particular moment.
I also believe a lot of writers take this approach because of the struggles they might have with narration, introspection, information dumping and world building.
But, I do believe there are more drawbacks to writing in a first person voice than there are in a third person voice. Let's work off of this diagram to see what I mean.