Office 2019 was designed for people who need Office without an internet connection.
Good news: The next version of Office 2021 is coming out this year and it will feature perpetual just like the old office.
https://www.pcworld.com/article/3608414/microsoft-wont-raise-prices-for-office-2021-which-may-ship-w...The reason why the internet connection is necessary is to validate that the user still has a valid license assigned. It must reach an internet connection once every 30 days before entering into what is called 'reduced functionality mode.' RFM allows you to view documents but you cannot create new documents or edit existing documents.
"As part of the installation process, Microsoft 365 Apps communicates with the Office Licensing Service and the Activation and Validation Service to obtain and activate a product key. Each day, or each time the user logs on to their computer, the computer connects to the Activation and Validation Service to verify the license status and extend the product key. As long as the computer can connect to the internet at least once every 30 days, Microsoft 365 Apps remains fully functional. If the computer goes offline for more than 30 days, Microsoft 365 Apps enters reduced functionality mode until the next time a connection can be made. To get Microsoft 365 Apps fully functional again, the user can connect to the internet and let the Activation and Validation Service reactivate the installation, though in some cases the user may have to sign back in first."
https://docs.microsoft.com/en-us/deployoffice/overview-licensing-activation-microsoft-365-apps#activ...There is a new feature that allows you to force Office to not check for activation for 6 months, but apparently it requires contacting a Microsoft sales representative according to the documentation here:
https://docs.microsoft.com/en-us/deployoffice/overview-extended-offline-access
