If my skin keeps getting better and then worse, should I change my skincare routine?

My skin isn't always in bad condition; it fluctuates frequently. It might be fine for a few days, only for the oil around my nose to suddenly become excessive and my cheeks to feel rough. So, when my skin is okay, I wonder if treatments are really necessary, but when my condition deteriorates, enlarged pores and skin texture become very noticeable, prompting me to look into skincare again.

I'm curious why my skin condition changes so much even though I keep using the same cosmetics.

In this case, would it be better to manage my skin in a way that maintains a consistent condition, rather than receiving treatment only when the problem worsens?

I am curious whether, during the consultation, you make a judgment based solely on the condition of the skin on a single day, or if you also consider how it changes over time.

I want to find out how to reduce skin fluctuations first, rather than just getting strong treatments.