When the show started, everyone was expecting it to goes seven seasons. I distinctly remember a TV Guide article on ENT when it was premiering where Dominic Keating was asked if he was ready for seven seasons. So, from the outset, there was a believe that ENT would have the same regular seven seasons that the previous Treks did under Berman.
But the fans were tuning out in droves, resulting in less episodes and a smaller budget, and eventually being moved from Wednesdays to Fridays. By the time ENT really got going from mid-S3 onwards it was too late. And S2 can largely be blamed for this, since the majority of the episodes that season were weak and amounted to pointless filler, and the soundtrack for that season was ridiculously uninspired and dull. Re-watching that season, it was hard to get through. S1 is considered a strong season and S2 just did not live up to the previous season. The fact that ENT was on UPN – a station that many in the US did not receive – did not help matters either from a viewership perspective. And nowadays UPN doesn’t exist anymore; its CW now.
I think discussions on potential ideas and episodes for S5 and beyond (and even better finales) has shown how much potential ENT had a series. Unfortunately, it was not reflected creatively in its original run, and that could be attributed to those above the writers. The vision that the powers that be wanted from ENT (remove Star Trek from the title, appeal to younger viewers, more action to get more ratings, premiere mere months after VOY ended and was still fresh in the audience’s minds) went against what the writers wanted (a show that was more primitive compared to TOS, at least a year long delay for the premiere – a necessity since this was a prequel and needed to fit in continuity), and hamstrung the series from the get go. That the powers that be didn’t even bother to give ENT a January premiere like VOY and DS9 before them, and then increase the episode order afterwards – instead choosing to give ENT a large episode order in the beginning and then cut the episode order as the series progressed – really says it all.
Add in BSG airing around the same time period and taking the risks that ENT should have from the beginning, and basically why should anyone tune in to watch ENT at all?
Considering the parallels ENT has with TOS in regards to cancellation, its surprising that ENT never received its own animated series like TOS or movies series or ENT: Phase II, to properly wrap up the series. We got the TOS reboot movies and new Trek series under Kurtzman – a nice parallel to the TOS movies and tv series under Berman – but there seemed to be a preference to make an animated series set in the 24th century with Lower Decks instead of with the ENT cast. Not even talks of rebooting ENT has come up at all. Passing references in DSC & the Kelvinverse is all that era gets now.
TPTB should have been professional enough to give ENT its fifth season as well as an advanced warning that S5 would be the last one. Considering it was still one of the most popular shows on the network at the time of its cancellation.