I grew up watching The Original Series over and over on BBC.
Plus the Motion Pictures.
Then, TNG finally reached Britain, and I was initially really hesitant about something that didn't have Kirk/Spock/McCoy in.
But I came to love it just as much, and realise now that it may have been one of the best TV series mankind has ever created.
I loved DS9, but toward the end of Season 7, I realised that the Dominion War was boring me. I think now, that I don't like the vision it presented as much as classical TOS and TNG. Everyone seemed tired by the end of it - Bashir and O'Brian were just following a routine.
VOY intrigued me when I first heard of it - and I stuck it out, and enjoyed it, until about Season 6, when it started becoming a tire like the Dominion War - I think the episode where I realised this was the one where The Doctor in one a big city-ship of some sort.
ENT, I originally had huge misgivings about, as did many people. I had lost faith in Star Trek, which had basically been my religion. But now, I realise it was a lot stronger than I gave it credit for - re-examining it, I love the show - I was way too harsh on Rich Berman and Brannon Braga.
JJ Abrams Star Trek XI initially seemed to me to be part of an awful trend in Hollywood of dumbing everything down and commercializing it, but I have learnt to enjoy his interpretation too.
So, after a dry spell, between ENT and 2012, I seem to have regained my lost faith in Star Trek.