Why do my images come out "fuzzier" than my peers?

So I'm realitvely new to PS, and I've been adding & editing lots of images to upload on a particular website, yet for some reason on that same site, some older and now retired admins have images to match, which not only were posted well over five years ago, but they tend to have a higher quality/definition.

Here's a few examples:

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- It's hard to tell, but the coloration looks slightly stronger in the older photo.

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- In the card you can scroll to the last two weapon skins, the green one is my edit, which looks very noticeable compared to the rest which look much more refined.

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- Same thing, the last edit is mine, the first two being another editor, who posted two much better and older skins.

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- Here's one more, in this one I updated the original skin & the second one, yet, the thrid one titled 'electro' has no "fuzz" in it.

I wanted to assume it was because I was uploading from my Ipad, using an app called Bazaart which is a more simplistic, although less versatile, version of PS, but now as I go about making these edits on my laptop, I find myself still in the same spot, getting these less than stellar edits; which I want to eventually archive.