Labels that had been agreed on by previous users would show on an "off limits" list and could not be used in that round. Some players thought that the game staggered appearance of the images, and that sometimes it took the first words typed by one player to form an "off limits" list for the other player. In other words, the off-limits words might be unilateral. This would explain the rather frequent circumstance when it seemed a partner could not think of words like "car," "bird," or "girl." Very rarely, at the end of the match it would become obvious that one image was different for the two players. One speculation is that this was simply an error, while another is that it was a test to see how quickly people would pass when their descriptions did not match. It may also have been a mechanism implemented to view cheaters, if the words for the different images were similar. At times, one user's computer would fail to load a new image or continue to display the previous image shown. Times likes these also called for a mutual "pass" on the part of both players.