Propellors for both turboprop and piston engines are specified to allow for full BHP (or ESHP for the turboprop) at the fine (low pitch) position.
Therefore, the props are set to this on short finals to allow the max BHP (ESHP) to be available in the event of a go-around.
Sometimes.
On large radial piston engines, the props are normally not moved to the fine pitch position, unless a go-around is desired.
This is to minimise, as much as possible undue master connecting rod bearing wear.
In addition, with some larger GA type opposed engines (TCM GTSIO and Lycoming IGSO series especially) the props are generally not set to the flight fine position on final either, as this minimises undue bifler pendulum damper (counterweight) bushing wear.