Why does a white stroke / outline appear in Photoshop on a cut out image?

Question

Photo

Firework! I cut out an object from a good quality photo. everything is ok: prntscr.com/iy2ppi
I reduce it to a small one and transfer it to another background and a white stroke / outline appears: prntscr.com/iy2rnx.
what is trouble?
or how else to deal with pixel teeth other than highlighting / smoothing, feathering, shifting the edge?
and through layers/edge processing?
(here is my example, no matter how hard I try, these teeth do not suit me: prntscr.com/iy2umz
here at 100% prntscr.com/iy2vpf they are still there)
Or you can’t get rid of them at such an angle. and you need to measure yourself
Is there anything easier? Am I doing something wrong in the first place?

Answer 1

firstly,
why consider these teeth under magnification - on a normal scale they are practically invisible;
secondly
, you lose an alpha channel somewhere along the way or the white substrate under the layer shines through

Answer 2

1. Check which interpolation method you have in the settings.
2. How do you carve? The latest versions have excellent settings that smooth out the edges and make the image look more natural on any background.