Users build their workflows around apps that use APIs.
Sometimes devs get bored/burn out/get a family/die/get a promotion, and stop building new features for apps. Sometimes, if users are lucky, they'll stay on top of security issues. But maybe, users install an app once and never update it even if it is getting updates. Which is risky, but if it works for them, whatever.
Service provider kills API endpoint.
App breaks.
User's workflow breaks. Worked yesterday, does not work today. :-(
Maybe, if the user is lucky, they connect with other users of the app, or users of other apps that are similarly affected, and they figure out workarounds, or someone creates a fork of the app(s) to use your new equivalent endpoint (if you even created one!) and, eventually, after much wailing and gnashing of teeth, they pick up the pieces of their workflow which you just broke and cobble together a new one.
Devs build apps that use APIs.
Users install apps that use APIs.
Users build their workflows around apps that use APIs.
Sometimes devs get bored/burn out/get a family/die/get a promotion, and stop building new features for apps. Sometimes, if users are lucky, they'll stay on top of security issues. But maybe, users install an app once and never update it even if it is getting updates. Which is risky, but if it works for them, whatever.
Service provider kills API endpoint.
App breaks.
User's workflow breaks. Worked yesterday, does not work today. :-(
Maybe, if the user is lucky, they connect with other users of the app, or users of other apps that are similarly affected, and they figure out workarounds, or someone creates a fork of the app(s) to use your new equivalent endpoint (if you even created one!) and, eventually, after much wailing and gnashing of teeth, they pick up the pieces of their workflow which you just broke and cobble together a new one.
But you caused them hours and hours of pain.
See also https://xkcd.com/1172/