I'm honestly surprised. I actually thought it would withstand at least another season, considering it was a spin-off of one of ABC Family's top-rated shows and aired directly after it, plus we got that cliffhanger and the endless amount of unanswered questions and things they setup within those ten episodes. Of course, there was definitely one setback that I feel made it suffer overall, and I don't think they thought it through as thoroughly as they could on how it would affect the viewership (something I feared as soon as it happened.) They sort of fixed it somewhat in the finale, thankfully, but they could have handled it way better from the start. I also agree with the producers that the timing probably was a bit too soon, which kind of goes hand-in-hand with that particular issue as well. Which brings me to my next point: if it's no longer going to continue it makes me wonder how certain things are going to be explained, and how loose ends are going to be tied up. Is Caleb going to return to Rosewood? What about his ties to Ravenswood, which he was heavily involved with? People will automatically think that this means he will magically reappear on Pretty Little Liars as if nothing ever happened, but then it wouldn't make much sense given that he had his own storyline in Ravenswood. I know some weren't happy with how things happened but this was important to his character, and I feel like they need to properly wrap things up with that before he returns to Rosewood and to Hanna. The town of Ravenswood is part of the Pretty Little Liars canon, so theoretically they could still focus on that even without there being a separate show.
In all, the series was a great ghost story. I'm probably in the minority, but I was genuinely enjoying and invested with what was going on. It had the right amount of scary and suspense that was done just right and I was loving the character ensemble. It's sad and disappointing that there won't be any more.
Just add this into the endless pile of shows that had loads of potential that I really liked that was canceled too soon. Le sigh.