Using CAPTCHA in Forms
Do you use any kind of CAPTCHA in your Forms? Having to fill in a random number / text helps prevent spam bots from filling in the forms and submitting them randomly - you did the same when you registered for here.
Here is a good tutorial to do so if you are interested:
New attack could make website security captchas obsolete. Researchers have created new artificial intelligence that could spell the end for one of the most widely used website security systems. The new algorithm, based on deep learning methods, is the most effective solver of captcha security and authentication systems to date and is able to defeat versions of text captcha schemes used to defend the majority of the world's most popular websites. Source 3e.
Security is meant to be broken right? I personally find those captcha puzzles annoying but its not to the point where I leave a site that has them because I understand their purpose.
A little obscured text I don't mind but the ones by Google are irritating to the max. "Find the buses" and when you do another one comes up "Find all the cars".
Captchas are a necessary evil that won't go away anytime soon. Better to have those than a 1000 spammers messing up your website.