I wouldn't call it luck. The difference between DayZ and all the once so called 'DayZ killers' is that the devs haven't abandoned the game yet (nor the initial idea that has always stood behind it). Don't get me wrong, there definitely were a lot of promising looking games out there, but no other studio has been able to create what DayZ is. Remember The War Z? H1Z1? Now those are what I call dead games.
Let's be realistic here, the only reason why there are still so many people crying about the devs mistakes (no, I'm not denying that there have been bad decisions from their side in the past) is because the game IS still alive after all it has gone through and people are worried that they'll never get what they've always wanted. That's exactly what threads like these are about.