I've recently started to pick up reading, and just finish Black Chalk. Spoilers Alert!

TL;DR: This book has a 3.6 rating on goodreads, but I loved it. Is something wrong with my reading? What makes a good book? How do I pick my next read if my taste differs from ratings?

I really like the book! The dual-narrative style of events unfolding on two timelines weaved together creates so much suspense. As the book shifts from one timeline to the other, I am always eager to finish the chapter and find out how the other timeline will unfold. It has a similar style as Dan Brown's book which really keeps the plot in suspense throughout.

The "spoiler" on the cover (Six students, five survivors) keeps you on the edge whenever something bad is happening, making you go "Oh no, is this it? Is this character going to die?". This is an extremely clever use of words on the cover page.

The inclusion of a different font to signal another layer of narrative is also brilliant, though it seems like much more could be done with such a device.

Question: Why is this book given a 3.6 rating on goodreads? Am i loving this book because I am an amateur reader and not well exposed? How do I "improve"?

I agree that the ending is rather "blah"... it did not tie up the loose ends in a fashion that lived up to the hype throughout the book. I really do like the characters though, but reviewers said there was a lack of character development. What does that even mean?

How do i go about finding my next read if i like a 3.6 rating book with substantial 1.0 rating reviews? Am I "reading" wrongly?

Ps: Please don't say "If you like it, its a good book...", I really want to learn how to appreciate books, and differentiate good ones from bad ones.