This is something I know that System Admins should be checking, defective PTFs in their partitions. As part of the latest Technology Refreshes, IBM i 7.5 TR2 and 7.4 TR8, is a SQL View that allows me to generate a list of defective PTFs. Previously this was only available in QMGTOOLS, alas I am not authorized to that in any of the partitions I have access to, therefore, you'll have to take my word that option 24, PTF Menu, then option 3, "Compare defective PTFs from IBM", takes you to the same information.
The View DEFECTIVE_PTF_CURRENCY is found in the SYSTOOLS library. It returns a list of defective PTFs that do not have the corrective PTF applied.
If this is the first time you have encountered this View I suggest you use the following statement to see what defective PTFs there are in your partition, and what columns of information are returned to you: