Softwware Update Deployment

Good morning i have a question on how the servers report on a compliance report.
we have started patching our servers this week and i have to tell you we never kept our servers up to date so we have lots of patching that is going on.
we notice that after installing the patches that are part of our update list our compliancy report is off by days on certain servers.
Meaning that we run the install of the patches, we run the compliancy report which then comes up compliant but after a day or and even 3 days we run the same report and the server is non compliant again. we notice that most of the servers is missing 1 or 2 updates.
we do run the scans manually to retrieve the update notification to see if any other update is needed, we then verify the reports.
why would it take so long for a server to see that itis missing an update from our update deployment?
 
 

Yes, I know this is an old post, I’m trying to clean up older posts that are unanswered.
Did you ever figure this out?