The blink element has been consistently criticised by usability and accessibility experts. In 1996 Jakob Nielsen described the element as "simply evil" in his Alertbox column Top Ten Mistakes in Web Design.[14] The World Wide Web Consortium's Web Content Accessibility Guidelines (WCAG) 1.0 state that content authors should avoid causing the screen to flicker or blink, noting that such effects can cause problems for people with cognitive disabilities or photosensitive epilepsy.[15]