By default, when you set up a redirect experiment, Optimizely blocks other redirects for 5 seconds so that you don't cause an infinite loop of redirects.

For example, this might happen if you set a redirect test from www.example.com/original to www.example.com/redirect and you have set URL targeting to a substring match for www.example.com. 

Because both the original and redirect page meet the targeting conditions, you will trigger an infinite redirect loop.

If you do not wish to have this 5 second check, and you are absolutely sure that your URL targeting does not include any matches for the site being redirected, then you can turn this off with the Edit Codefunction by changing the value '_optimizely_redirect' to '_optimizely_redirect_no_cookie'