Ptosis correction increases the volume just below the brow, on top of the crease.
After surgery, this can leave the upper eyelid looking thicker and puffier.

If the eyelid was already on the heavy side preoperatively, surgery can make it look heavier still.
I have written about this before, and it may help to read that earlier post.
Removing the ROOF (retro-orbicularis oculi fat) along with some of the orbicularis oculi and the connective tissue at the upper lid does soften the post-op fullness to a meaningful degree.
That said, getting to a truly thin eyelid is rarely possible.

Here is the same patient about six months out.
Some thickness remains, but nothing that looks unnatural.

The SMFAT layer needs to be excised carefully.
If too much bleeding pools during that step, or if scar adhesions form, the patient ends up with a multiple-fold (so-called triple eyelid) deformity.

