It depends.
I would say don’t be too concerned with the number of sessions. There isn’t a one-size-fits-all solution because we are all starting from different places based on our life journeys and experiences. If it takes you nine sessions to get to the place you want to be that doesn’t mean that you’re “slow”, “not spiritual”, or “not focusing hard enough”. Or, on the other hand, you may have had the intention of booking four sessions but feel after only one that you are in a good place on the subject you were looking for insight or greater understanding on.