Well.thats normal. They use that to avoid bots. Other than that here are benefits of captcha
Blocking Spam Emails | Don’t you hate it when you go to open a seemingly important email only to find that it is spam? Yeah… me too. If you want or need help help blocking those pesky emails, then using a CAPTCHA submission form at the end of your contact page/form can help to lower the number of junk emails that wind up in your Inbox or Spam folder
Blocking Spam Comments | Perhaps the most irritating thing a website administrator has to deal with is spam comments. Sure, plugins like Anti-Spam Bee or Akismet can capture those bot induced spam comments and send them to the spam folder in your WP dashboard, but they can’t actually stop such comments from being submitted. Using a CAPTCHA form on your comments may be slightly tedious for your commenters’, but using it can eliminate a large chunk of those spam comments from even happening in the first place. This means that you can spend more time on the good bits of running a WordPress site, and less on comment moderation — we all hate that part.
Topic: Is it really useful ReCaptcha? - page 2. (Read 1230 times)
It's to get rid of bots so the site will not be exploited. It also is necessary so the site will not clogged with too much traffic. I don't see why solvigthe captcha every now and then coul be a bother.
I mean, most of the time once a day is renewed, or every time you change the IP.
Because, as you may know, the first time it is used you only have to click and the green check mark appears, but when you use it often, you have to choose the diferent images.
Is not this a weakness, or could be an exploit?
It isn't necessarily the first time you use it during the day... I've had to enter a couple of ReCaptcha's this morning after being offline overnight, and had to click images... however, about 15mins ago, I was on a site trying to sign up and had to do a ReCaptcha and it just accepted the click and gave me a green tick.Because, as you may know, the first time it is used you only have to click and the green check mark appears, but when you use it often, you have to choose the diferent images.
Is not this a weakness, or could be an exploit?
I suspect it is some random combination of time, IP, time since last captcha etc that they use to decide if you get the "free pass"...
Otherwise, as you say, it would be exploitable simply by rotating through different IPs using proxies (or exploiting your ISP if they assign a new IP every time you reconnect to the internet) which would make ReCaptcha a bit useless...
As far as Captcha's go in general... I find them very annoying... especially those SolveMedia ones... sometimes it just looks like crazy scribbles made by a 3yr old with crayons and you just can't read the letters... I've actually given up on a couple of websites because their Captchas were simply unreadable (I clicked the change captcha button like 30 times) and I couldn't sign up an account
I understand why sites use them tho... but they need to at least make them human readable!
Captchas are very Good Services offered by many Companies like Google, Solvemedia etc.
And Captcha prevent our Website From Bots and It is Very Useful For Faucet owners because they have to prevent their Faucet From Bots.....
And Captcha prevent our Website From Bots and It is Very Useful For Faucet owners because they have to prevent their Faucet From Bots.....
Captchas are just there to provide protection against bots. Bots can't be used if they can't actually get past the captchas. 
I mean, most of the time once a day is renewed, or every time you change the IP.
Because, as you may know, the first time it is used you only have to click and the green check mark appears, but when you use it often, you have to choose the diferent images.
Is not this a weakness, or could be an exploit?
Because, as you may know, the first time it is used you only have to click and the green check mark appears, but when you use it often, you have to choose the diferent images.
Is not this a weakness, or could be an exploit?
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