A friend of mine decided to get a tattoo this weekend. Moreso, he decided to get it in Latin.. without asking anyone for some help with proper translations or anything!

So, in the hope of making sure he hasn't made a terrible, terrible mistake, could someone let me know if his decision to get 'neutiquam erro' tattooed in fancy letters on his arm was at least grammatically correct, if not in generally poor taste?

Thanks in advance!