I tried having my ears pierced twice, plus that spot on top of the ear (whatever the name of that is), as well as my bellybutton. They would get infected instantaneously, no matter what I tried, so after a few weeks of trying to keep them, I gave up.
Now, when I went to get my tattoos (I've got 2 of them), they were both done in solid black ink. They turned grayish within 2 weeks. My doc said that my body was rejecting foreign objects (the piercings, the ink), and that I should just stop while I'm ahead.