Hi Hersi,
It does not have to match.
You can create a sales order for 7, reserve all 7 and your work may still not be 7.
Let's say you have an on-hand qty of 7 for item A, in 7 different warehouse locations (L1, L2, L3 and so on..)
You might reserve 7, release 7 but work will not be created for 7 if you location directives do not hit all these locations.
It sounds like there is either an issue with location directive setups or a mismatch between directive codes of work templates and location directives.
Could you please go through your work creation logs, check your location directive and work template setups?