I’m not quite sure what you are asking, but no one submits for a 9.9. There’s a reason the highest prescreen is for 9.8. Anything higher is rare... and gravy!
I can tell you, in general, for me a 9.9 has to be centered virtually perfectly, no spine stress and only 1 tiny corner issue can be present... and by tiny I mean like the size of a pinhead. A 10 wouldn’t even have that as it should be flawless to the naked eye.
By comparison 9.8’s can have several more tiny defects such as a few light spine stress or 1 moderately sized one.
Most books are not worthy of 9.9 on printing defects alone, such as tiny production tears at the spine corners, production edges creases, and on ultra moderns, production bends on the front and back cover. Many brand new books also have light circular indents near the corners, like the size of a nickel.
Hope that helps people know what to look for... in general!
Oh, and Transformers #1 is notorious for a production rough cut, usually to the top edge of the back cover.