Then it means the car had so bad an accident that it was not even movable at all.
Second scenario is that car had some malfunction with transmission or engine or something which rendered the car non-movable
Thirds scenario is the car had a minor/major accident but was not repaired and imported without repairing the damage. If the damage is repaired inside Japan be it replaced parts or proper denting painting etc it is given R grade. If it not repaired and exported from Japan in the un-repaired state then no grade is given
If the auction sheet has no grade stay away from that car. Dooooooor se bhi mat sochain woh gaari lenay k liye. 100% guarantee se mein keh sakta hu k beshak minor damage wali hogi lekin repair Pakistan mein hui hogi and apko pata hai kaisay repair hoti hain idher gaarian desi tareeqay say so please stay away from that car