It's get better. That means "It is get better." My computer won't even let me type that sentence out. It gives me the red squiggly lines. Actually, I get a lot of those. I'm sure they meant "it gets better," but jee louise, who are they trying to convince, us or themselves?
The great thing about a travesty like this is that it takes two people for it to happen. Either the customer gave the tattoo artist this incorrect sentence and the tattoo artist just went with it, or the tattoo artist messed up and the customer just let themselves get the dumbest tattoo on Earth. It's also totally possible that they both didn't realize the mistake. The person could still be out there thinking the tattoo is right just because everyone is too polite to say anything.