Out of five edit suggestions, only one was approved. That is 20%, a very low percentage. Since I am not a cooking expert, but I like editing English, I thought that's an useful way to get points. Note that you spend some time to edit. I feel like I am blocked to do edits, or that the policy is a tolerance for English errors.
I don't think I can actually see the rejection reasons used for your edits, but I strongly suspect that most of yours were rejected as too minor.
The description basically explains it:
This edit is too minor; suggested edits should be substantive improvements addressing multiple issues in the post.
It's not that we don't like to see proper spelling, grammar, and punctuation. We do. Some of us (myself included) are veritable sticklers for this in regard our own posts and will often rewrite other people's posts completely (or at least the titles) to make them coherent.
However, adding a few apostrophes to the word "its" really does not go a long way toward making the post more clear or readable.
If somebody's writing style is absolutely atrocious, please, fix it. But don't nit pick over image sizes or italicization of terms. I'm sure your intentions are entirely positive but to most of us it appears to be editing just for the sake of editing.
Most edits here are, in fact, approved. Yossarian approves about 2/3 of edits, I've approved over 80% of the ones I've seen. An edit really has to be quite trivial or even wrong in order to be rejected.
Here are two examples of recent, quality suggested edits that were approved:
As you can see, these both include significant changes and make the posts far more concise and readable.
By far the most effective way to get your edit rejected is to correct very minor issues while leaving behind major ones. Examples would be fixing a few capitalization or punctuation problems in posts that (still) have several grammatical errors or worse, are factually incorrect or even nonsensical walls-of-text.
If you don't wish to have your edits scrutinzed this way, then contribute quality answers (or questions) until you have 2k reputation; then you can edit freely without your edits needing to be approved.