What feature is essential for the user-friendly deployment of applications in Alibaba Cloud?

Function Compute is crucial for the user-friendly deployment of applications in Alibaba Cloud because it offers a fully managed serverless computing service. Users can write and upload their code without worrying about the underlying infrastructure, which simplifies the deployment process significantly. This allows developers to focus solely on writing application logic while Function Compute takes care of scaling, availability, and server management.

With Function Compute, applications can be run in response to specific events, which makes it highly adaptable and suitable for various use cases, such as web applications, data processing, and API backends. The pay-per-use model further enhances its user-friendliness, as developers only incur costs for the compute resources consumed during the execution of their functions, leading to efficiency in both resource management and operational expenditure.

In contrast, while other options like Elastic Compute Service (ECS) also facilitate application deployment, they require more management of virtual machines and infrastructure setup, thus lacking the same level of user-friendliness as Function Compute.