Helix was a weird one. The first discussions took place way back in 2008, two years before I joined. It was unceremoniously ditched when the economy took a dump. Design work ramped back up in early 2011. Active hardware development began in late 2011, for a planned release in the summer of 2014. The touchscreen and mobile editing were ditched in favor of cap switches and desktop editing around 2013, much to my chagrin. This and a whole lot of other drama resulted in pushing back the launch to June 11, 2015.
Products has designs that, if ever released, may not see the light of day for a decade or more. That doesn't mean we're slow; we just have way more ideas than we can actively develop. I guess that's better than Engineering tapping their feet, going "Okay, c'mon. What are we making next, guys?!"