Arris -- a lesser know manufacturer of routera and other network equipment -- is another company, who is hiring a complete morons as a developers.
These idiots implemented CAPTCHA it in... router's control panel!
So, here it is, in case you wouldn't believe it:
I have never seen any kind of software or service where I'd be required to provide CAPTCHA to save settings in my very own profile or device's configuration!
For those, who doesn't catch the irony -- CAPTCHA is supposed to differentiate regular human legitimate user from automatic spambots. So, if a spambot gains access to my router's configuration (meaning: that a spambot has my login and password and is able to login) then I don't give a shit, if it is stopped by CAPTCHA from saving configuration or not. I am already screwed (bot has my password!).
In simpler words -- adding CAPTCHA to configuration software brings absoluty nothing in terms of increasing security, but it does increases user irritation a lot.
In even simpler words -- have you ever seen CAPTCHA in any place, which you can access only after login?