Some combinations of burner and disc work better after 1 or more full erases. The phase change material sometimes has to be "conditioned" (don't ask me what that really means
c't usually does a "burning cascade" in their tests- writing e.g. 1/8, 2/8 ... 8/8 of capacity to a virgin disc with a quick erase in between. So if they see a jump in error rates at one of the cascade boundaries, they make the recommendation to do 1 or more full erases prior to using.
So much for theory. I just use them out of the box.
I used to do full erases (habit from CD-RW usage), but now mostly do a quick erase with no noticeable adverse effects. The time difference < 1 min. vs. 15 min. is just too great.