Image sizes do not correspond with media settings?

Hi @sailordudes,

Hope you’re well ??

1) When I look at the wp-content folder I see that WP smushit generates many images with the size in their file name, but none of them have the 600×400 format. Why not?

WP Smush doesn’t affect your images during upload or what image sizes are getting uploaded, Smush is optimizing images after they have been uploaded and the thumbnails are created.
I believe that this is something that you should check with your theme developers.

2) How does WP know that it must choose a “smushed” image instead of the one that I originally uploaded? Or in other words, what logic is applied to choose one of the smushed image sizes over the image that I originally uploaded?

How smush works is that it sends your image thumbnails to our servers where optimization is performed and after that it sends them back to your server where your original thumbnails are replaced with the optimized ones.
When you use thumbnail on your site it will use optimized one as the original thumbnail is no longer user at all.

Note that I was referring to thumbnails above, that’s because original images are not optimized in free version, that’s because themes/plugins usually have needed thumbnails predefined and that what Smush will optimized.
If you add full image in content then it will not be pulling optimized image since there is no one.

Hope this helps ??

Cheers,
Predrag