Why do make me to wait for the entire page and then redirect when I am already logged in?

Why do make me to wait for the entire page and then redirect when I am already logged in?

Dear Zoho Single Signon Team,

Why do make me to wait for the entire page and then redirect when I am already logged in? I think you can quickly detect the logged on cookie even in the main page instead of waiting for the Zoho SSO IFRAME right?

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Deepak Vasudevan
http://thamizhththendral.blogspot.com/