It’s a valid question. There’s an accumulation of defects: Besides your aforementioned color breaking spine stresses, there’s tics on the BC, the top edge of the back cover has dings, the top left corner of the back cover has been slightly impacted, there’s a color transfer or soiling by the price on the front cover, there are two slight indentations on the FC between the R and O of ROM and below the S in Spaceknight. And that’s with my untrained eye, others might see more. Now some of these defects can be pressed out and others (like color breaking creases) cannot be fixed. As the book sits, 9.0 or possibly 9.2 is a fair grade.