When signing up and making a mistake, for example entering the wrong captcha, which will cause the page to be reloaded, then the values Language, Currency and Country get set to their "defaults", which are: English, USD and Afghanistan and a weird timezone (International Date Line).
Many people will not look twice over the form after they already entered their correct information and will just notice the "red box" (captcha), enter the captcha correct on the second try and then Eduardo from Spain who chose EUR and GMT+1 will become Eduardo from Afghanistan with USD and timezone set right at the Date Line.
Thanks!