The iconic meeting took place in 2008. In it, the committee made the hard decision: ECMAScript 4 was dead. A new version of ECMAScript was to be expected, and a change in direction for future work was drafted. Brendan Eich broke the official news in an iconic email.

Source: The Real Story Behind ECMAScript 4

“Futures that might have been” are always fascinating. This article is about why there was never truly an ES4, just ES3 and then ES5.