Thought of the words of wisdom for gym / lifting weights:

You don’t get stronger while you work out, you get stronger while you rest.

Something like this is also true for improving vision. You note the improvement in centimeter / eye chart / distant landmark as your eye is adapting to the increased challenge, when the reduction is still new.

But the actual sustained improvement happens after, when that improvement appears consistent.

Leave 3-4 months between diopter reductions, even (and especially if) things seem improved and consistent even after a much shorter time span.

Also see the 10 Most Common Mistakes.