We are using SNOW to locate unused software where the software has been installed at least 90 days. Then we use SCCM to remove the unused software. We are seeing in SCCM that the software install date is different than what SNOW is reporting. i.e. - we recommend removal of software A as SNOW shows it was installed in Nov 2017 and never used, but SCCM shows it was installed in Jun 2017 (and in some cases is being used).
What would cause the difference in install date detection?