I uploaded a profile pic and It kinda became worse quality than It was before.
Most Helpful Guy
yes they do.
just compare you pic with the original one you uploaded:
for mine avatar:
original: 1000x1346 (627kB)
I saved it as JPG with the compression set to 90
GAG: 446x600 (46kB)
so the resolution got removed by 80%
now if I save my original pic at the same resolution with the compression still set to 90, the file size will be 132kB. So you can see that the compression is much higher too, which means that it loses detail (less sharp, artifacts, etc).
To get the picture to 46kB, I would have to set the compression level to 45-50, so much higher. At that level there is definitely a visible quality loss