Well, no, but mostly because it's expensive.
I would say do some family research first and see how far you can go back.
I'm half Spanish (as in Spain) and we have this odd family name from there that sounds Irish, and not Spanish, but it's no lock that it's Irish.
Question is, how far does this genetic DNA go back, like 1500+ years, or just say 400 or so?
People do get surprised. I've read or seen stories about African Americans who have the test done because they want to see what part of Africa they're from.... and it turns out they're part Anglo. And there are people who think they're going to discover their related to some dead president or maybe find that missing anglo heritage and.... they're part Arab or African, etc.