Collet and body die order of use

[BeefyT11]

Because you don't size the case until it needs to be sized.

My understanding was in this scenario cases were being sized with both dies every firing. I guess that's where my original question stemmed from why size the neck before sizing the rest of the body?

 

[Straightshooter1]

"When you say "body die", are you referring to a FL sizing die?"

No. A body die resizes the case body and bumps the shoulder (if desired) but does not touch the neck.
FL sizer does those two things but also sizes the neck.

Gotcha. I just wanted to be clear to be sure I understood correctly as some people say that referring to FL sizing die.