Microblading (manual) can last anywhere from 6 months to 1 year, usually.  Microneedling  (machine) can last anywhere from 1 to 5 years, typically, before needing a touch up.

Cosmetic grade pigments are usually made with an iron oxide base, as opposed to the carbon-based body tattoo pigments.  Iron oxide-based pigments are not as stable in body long-term, nor fade-resistant to UV sunlight as the carbon-based pigments.

Sunlight is tattoo’s worse enemy!  So, a person’s lifestyle, environment, and amount of direct sunlight exposure both with and without sunscreen will greatly determine how soon a touch up is needed.