The hardware used for Processing Stations has a considerable impact on FlexiCapture performance. A Station launches 1 executive process per each CPU core. Therefore, more CPU cores allows for the processing - more tasks can be run simultaneously.
If you specify in the"Maximum number of processes" settings a value lower than the hardware limitation, then the program will use the specified number and nothing more. This could be helpful if the PC is used for some other activities, so the processing station service should not use too much resources. By default this field contains a value equal to the hardware limitation, so the station is allowed to use all cores.
Please find more details on the subject in the section of the online FlexiCapture 12 Performance Guide: http://help.abbyy.com/en-us/flexicapture/12/performance_guide/pg_introduction