I think the mods and/or the common dumpers should decide, but here my 2 cent about it:
In gerenal it's the best if you have a disk without any errors. But maybe someone has the same disk, but with different damaged tracks, so in the end we could compile a complete, errorfree enty in the db/dats.
Since there are not so many german dumpers, it could be difficult/expensive for them to get some german titles in perfect condition, in this case it could be helpful to dump a disk as far as you can, and somebody else does the missing tracks.
This could also helpfull for some of the exotic japanise/asian titles, which are even harder to get in a dumpable condition.
After collecting all the needed infos here in the forum, the disk could be saved in the db.
But, as mentions, some of the stuff/usual dumpers should decide.