How does worker/work pools deployment in Prefect work

hello everyone

Based on the text and the arrow depicted in the provided picture, it appears that communication between the two servers initiates from the execution environment (workers) and goes towards the workflow (Prefect API). This raises the question of why the communication doesn’t start in the reverse direction, where it might be more intuitive for the Prefect API server to initiate communication and send requests to the resources.
One might naturally assume that the Prefect API server should be the one to begin communication and request resources.
thanks