I'm not a critic and I'm just going to be honest by giving my opinion.
It's somewhat fast-paced, and it keeps you hooked every episode. It may be "cheap" jumpscares for other people but it still gets me and was still terrified.
I don't easily get scared, but there's something about this one that scares me.
There's no introduction, just focuses on what the story actually tells. It gets scary as the story unfolds.
Flashbacks episodes were definitely needed for this one, it didn't ate up the whole season and just gave you a little bit of it when it was needed. It was not forced and just gave everything what you actually wanted or what is needed for the story to unfold on how or why it started. It raised some few questions but I guess the answer were obvious ones or plot holes.
The horror vibe is uncommon, but it uses the "hollywood" jumpscare type of thing. But the story is interesting. The actors and actresses did a great job. It's creepy, eerie and definitely better than the Annabelle, Conjuring 2 & 3 and other horror movies as well.
I guess you can also say that this series has "butterfly effect". You'll understand it as the episode goes.
The ending was pretty questionable as it doesn't make any sense at all. It could've ended on that season but I guess they want to expand the story which I think is not a good idea. But overall, it's sad, creepy and eerie. Not top-of-the level horror film/series but it's a recent horror series that is pretty decent. We barely got a decent horror films or series nowadays. This is worth a watch. 8/10