Question on the SSH-2 standard

I am getting stuck trying to understand the nuances of the SSH-2
standard in a number of cases. For instance, in section 7 of RFC 4252,
when describing the client's response to an SSH_MSG_USERAUTH_PK_OK packet
received from the server, the RFC reads:

"To perform actual authentication, the client MAY then send a
signature generated using the private key. The client MAY send the
signature directly without first verifying whether the key is
acceptable."

So, since the client just MAY send a signature, what happens if
it doesn't? My assumption is that the authentication won't be successful,
and that the server will just drop the connection. Is this correct?

.

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