Tattoos are just a shitty fad, they don't hold the true value or meaning that they portrayed in more ancient times (you don't need a tattoo in the office space, at the construction site, or at McDonalds.)
Most people who get tattoos are bouncers, people who have no clear direction in life and don't think about the outcomes of their decisions which is why the majority end up regretting getting them after some time.
These people for all I know are mostly egocentric assholes who pretend to be rebels (even the intelligent ones) and don't give a fuck about what other people think, in their minds getting a tattoo is the right thing even if their decision was the result of peer pressure, being high, lack of self discipline, ignorance, or mere stupidity.
Most of these people ultimately get tattoos to show off or get some sort of attention, sure they may think it is a form of art but no one really gives a fuck about them (except their little groups of tattoo freaks), your skin is not a damn canvas, tattoos simply are conversation starters and nothing more. People get used to them after a while, and even if they still hold their original value or meaning these people will eventually get bored and want to get a new one, if the contrary is true most of them will probably regret it in the future.
There are better ways to remember someone or something and that is by using your damned memory, yes the one you use to remember how to clean your ass after taking a dump. If you can remember how to clean your ass, do you think you'll forget that special something/someone if you don't get that tattoo? Be rational.