When the WhatsApp Business API first launched, businesses or their providers had to install and maintain the API client on their own infrastructure. This was the On-Premise model.
Self-hosting gave more control but required servers, updates, and engineering effort. New features also arrived on the On-Premise API later than on the cloud version.
Meta has announced the sunsetting of the On-Premise API and now directs all businesses to the WhatsApp Cloud API, which is hosted and maintained by Meta itself.
