as you grow older, your skin will definitely start to sag and stuff. but that's just how things go.
the best thing is to tattoo something that means something/a lot to you so that you won't regret it later in your life. to me, personally, i'm not discouraging it or anything, but i think that tribal tattoos are not worth it. unless you're into the whole tribal culture. heh. NO OFFENSE AH!