Does it matter If the Game I'm trying to burn is scratched up,when It comes to making a copy?

[StarWarrior]

I've noticed that my New Original games that I've recently bought w/No scratches at all.Make perfect copies useing nero 5.5.

However some of the older Original games in my collection that have a considerable amount of scratches,will stop at like 60-80% on the read process and not go any further making them uncopyable.
Even though they still play fine in my PS1.

My question is simple-Am I correct in assuming that the CD-RW Drive is more sensitive than a PS1 whenever It's comes to reading games,and thus a really scratched up but fully working game can't always be read properly and copied?

And one more question:Will a CD repairing device like the scratch doctor which repairs and prevents Skiping,work in making my scratched up game readable on my CD-RW??