EFA with a fixed number of factors

#1
Hello
I posted this a few days ago on Psychology Statistics section of the forum but nobody answered. I thought maybe I posted it in the wrong section.
I'll be very thankful for comments.

When should one use exploratory factor analysis with a fixed number of factors?
If we know a priori the number of factors, then we use confirmatory factor analysis (CFA).
On what basis do we decide if we need EFA with a fixed number of factors or CFA?
Best
Anthony