The Business Process Output Delete Global Change in Database Growth Management has a criteria to let you filter the deletion to: "Delete output tables for all but the most recent x runs."  

We expected this to delete all but the most recent X runs by instance of the process filtered in our selection, but after testing and confirming with support, the global change will delete all but the X runs by process.  We do not find this helpful, and would like this changed.

Example:

We have 1,600 instances of export processes.  We would like to delete all but the most recent 1 run by instance so we are left with 1,600 output tables.  Currently, if we run the global change we would be left with only 1 output table for the single most recent run of all 1,600 export processes combined.