What is the standard for feeling that your skin has improved?

I have been consistently managing it, but I am not sure if it has actually improved.
I'm wondering if I should consider it an improvement if the skin troubles decrease.
Sometimes I feel like my skin texture has become smoother, but it also seems to be temporary.
People around me say my skin has improved, but I'm not really sure myself.
When comparing the photos, it seems like there is a difference, but then again, it is ambiguous.
They say that skin changes appear gradually, but it is difficult to feel them.
I am also curious to know what level of improvement should be considered.
I would like to know if there is a way to objectively assess the condition of the skin.