How often should I receive treatment to maintain the effects of the blemish treatment?

As I consider getting treatment for blemishes, the thing I am most curious about is how long the effects last.

Even if my skin tone is somewhat evened out, I am worried that blemishes could reappear due to UV rays or lifestyle habits, so I am wondering if I need to continue getting treatments at short intervals.

Once the blemish treatment shows good results, do you tend to receive periodic maintenance treatments? Alternatively, I would like to know if there are cases where the results last a long time simply by using sunscreen or maintaining a brightening routine after a few blemish treatments.

I am also curious if the treatment cycle for blemishes varies significantly depending on individual pigmentation levels and skin types. If it is possible to start with intensive care and then receive treatment only when necessary, I would like to do so.