Same as Azure Functions. Internally at Microsoft everyone knows that it’s completely broken and they don’t understand why customers use it either. Apparently it was due to an extremely dysfunctional team and certain team members.
Have a play with AWS Lambda or Google Cloud Functions, then compare that with Azure Functions and you might wonder if what Azure has done is even remotely “serverless” FaaS or just a huge messy clusterfuck of an App Service which is billed per second and overly complicated to manage and observe.