Bruce Tognazzini, a usability consultant who worked for Apple in the 1980s and 1990s before Mac OS X was developed, wrote an article in 2001 listing ten problems he saw with the Dock. This article was updated in 2004, removing two of the original criticisms and adding a new one. One of his concerns was that the Dock uses too much screen space. Another was that icons only show their labels when the pointer hovers over them, so similar-looking folders, files, and windows are difficult to distinguish. Tognazzini also criticized the fact that when icons are dragged out of the Dock, they vanish with no easy way to get them back; he called this behavior "object annihilation".