SharePoint Site Storage and Quota Limit Ambiguity

Hi All, I apologize if this was posted before. Does anyone know why SharePoint storage size numbers are different in the SharePoint admin center compared with checking Get-SPOSite StorageUsageCurrent value? Microsoft states there is 25 TB available per site.
https://learn.microsoft.com/en-us/office365/servicedescriptions/sharepoint-online-service-description/sharepoint-online-limits

In this article they show the total storage is 25.6 TB. If you check the storage metrics under site settings, you see 25.6 TB

https://learn.microsoft.com/en-us/sharepoint/manage-site-collection-storage-limitshttps://techcommunity.microsoft.com/t5/sharepoint/understanding-this-usage-metric-total-sharepoint-storage/m-p/3620651

If you use the script to monitor SharePoint storage it uses the StorageUsageCurrent value. The script also references storage quota which is 26 TB. Why isn't this 25 TB?

Does anyone know if the hard limit is 25 or 25.6 TB and why is the quota limit higher than the hard limit?