DO Load Balancer: what happens if a server becomes unavailable before it is detected as unhealthy?

I mean, suppose that the healthy check is performed every 10 seconds and the server is removed from the list after 3 consecutive failures. The whole process takes 30 seconds. What happens in that 30 seconds if I turn off a server or when the server produces failures? When a connection from the load balancer to the server fails, does the load balancer retry automatically with a different server? Or does it return an error to the client?

I think that this question actually refers to two distinct scenarios:

1. TCP connection fails (e.g. the server is turned off)
2. the server is returning HTTP errors (e.g. misconfiguration) <- I’ve found the answer for this second scenario: the load balancer can’t do anything because has no way to detect it, obviously