The Fox drama Terra Nova debuted last fall with Steven Spielberg as producer, a $20-million pilot, CGI dinosaurs, a relentless promotional campaign, and perhaps the most buzz of any new series. Yet the show premiered to a so-so 9 million viewers, and averaged a not-stellar, not-abysmal 7 million viewers for its season. Now, Fox has officially decided to cancel the ambitious series. What went wrong? Here, four theories:

1. The story was bad
In the lead up to its debut, Terra Nova bragged effectively about its expensive effects and launched a publicity campaign "that could only have been more intense were one of the dinosaurs played by Katharine McPhee," says James Poniewozik at TIME, but the show, quite simply, wasn't any good. It was essentially "a C-grade time travel story that would make Ray Bradbury chortle dismissively," says Darren Franich at Entertainment Weekly. As the series trudged along, it continued to grow detrimentally self-serious, and was brought down by baffling conspiracy plot lines.

2. "Big movie-style budgets don't work on television"
As Transformers and a bevy of poorly-written, effects-heavy blockbusters have taught us, movie audiences are willing to sit through essentially bad films because they "can't help but be captivated by the sheer amount of money onscreen," says Franich. Though the funds channelled into Terra Nova were disproportionately large for a TV show, they didn't translate into the same hypnotic sheen; the show still "looked terrible." From the spotty CGI dinosaurs to the cheap-looking sets, the show couldn't "compare to a typical two-hour blockbuster movie."

3. It tried to be too many things
The show's executive producer avowed that Terra Nova "is for everybody. Everyone from my kids to a gamer to my dad will love this show." What a doomed oversell, says Tim Kenneally at The Wrap. No show that "promises to be everything to everybody" could possibly deliver. Indeed, the series' kitchen sink approach baffled viewers. "Was this a family drama? A prehistoric action-adventure series? A sci-fi program?" High turnover among the show's writers didn't help. "Too many cooks and too many ingredients left Terra Nova veering week to week" between environmental preaching, Jurassic Park ambition, Lost-like conspiracy theory, and underdeveloped character drama.

4. The age of sci-fi on TV may be over
Attempts to replicate the success of the epic Lost have failed, says Poniewozik, leading most networks to focus on "small-scale, real-world shows" with minor sci-fi twists or fantasy themes, like Person of Interest, Alcatraz, or Once Upon a Time. Viewers have been responding, turning those shows into modest hits. The "epic-scale, effects-intensive" Terra Nova, on the other hand, was out of step with trends. The question moving forward, says Alyssa Rosenberg at Think Progress, is whether networks can "think more creatively about communicating" futuristic stories "without using a lot, or any, special effects."