[Exim] "noerror" in filter file: What does it mean?

I'm analysing a problem with one of our user's forward files... I'm not
sure all of a sudden what the following means (from the Exim 3.3x filter
spec):

However, if the filter command which sets up a delivery is preceded by
the word `noerror', then errors for that delivery, /and any deliveries
consequent on it/ (that is, from alias, forwarding, or filter files it
invokes) are ignored.

I've somehow been under the impression that "noerror" would mean not
getting bounces to the ultimate sender on forwarding address delivery
failure, but is seems now that I've been wrong... So what exactly does
it do?

- Toralf