Why The US Navy Cancel The Stealthy A-12 Avenger II Program?

As sixth-generation fighter jets come closer to development and take fighter jets into a new era of warfighting, the world is reminded of the futuristic fighters that came so close and yet never were. The A-12 Avenger II was to be an all-weather carrier-based attack aircraft and stealth bomber for the Grumman A-6 Intruder for the US Navy. While it faced the typical cost overruns and delays, many felt it was showing promise and was about to go into production. And then, it was canceled. But why?