why openssh tries `none` authentication method

[Logu]

Hi,

I would like to know the significance of trying `none` method during 
authentication sequence. Is there any way to avoid unnecessary trying of 
this none authentication method first.  We are writing a patch to log bad 
login into btmp for all traditional authentication methods supported by SSH. 
The `none` method increments the authctx-failures and we are facing problems 
with this.

-logu