Does the shape of the lips change dramatically even with just a small amount of filler?

My lips are on the thinner side, so I've wanted to add just a tiny bit of volume to them for a while.

However, when looking at the before and after photos, there are cases where the change is greater than expected, so
I couldn't get a sense of what a natural amount was.

Especially, rather than thick lips, I
I want my lip line to become slightly more defined when I apply lipstick.

I wonder if it would be better to show you a photo of the shape I want from the beginning.
I'm also wondering if it would be better to just explain that I want it to be natural.

How did those getting lip fillers for the first time convey the look they wanted during the consultation? 💋