Why do parameter jumps appear between two identical keys in Premier Pro?

Question

Adobe Premiere

I specially recorded a video so that you can see what and how I am doing and what is happening
https://youtu.be/HLvTXbaAs9o
I put 2 KK (keyframes) with a horizontal value of 450. Between them there is an increase in the number 450, then a decrease. Why does it work like this?
Yes, then I have other CCs and the parameters change there, but where does this increase come from, as if there is some kind of phantom CC with a value of 460 or something between the two new CCs.
It used to work that way too, it always worked that way. Already tired.
What to do ?