NaCl predates asm.js/Wasm by 2 years: it wasn't always an option

Here's a timeline:

  2011-10-16: Native client released
  2013-03-21: asm.js released
  2013-06-25: Firefox 22 released with asm.js support
  2013-07-17: Chrome 28 released with optimizations for asm.js
  2015-06-17: WebAssembly released
  2017-06-30: Google announces switch to Wasm.

When do you think was a Good time for Google to switch tracks?