How Important Are Emotional Connections With Characters?

Along with so many other layers to a novel, giving your characters a strong emotional draw is so important. I'm working on adding more into my WIP so my readers will have a stronger personal connection to my characters. Thinking back to books I've read, some lacked emotional pull though strong in other areas and lost me, while other books may have lacked in other departments but had such strong emotional angles that I couldn't stop reading.

When it comes to the former, A Poisoned Season by Tasha Alexander instantly comes to mind. I loved the premise, loved the setting, but could not for the life of me care a lick about the main characters! I actually felt more for the minor characters Jeremy and Cecile than the protagonist and her boyfriend (whose names I've now forgotten). I regret that because the plot was intriguing and fairly well-executed. But I've never felt a desire to read more of the series.

As to the latter, I think the Kathryn Swinbrooke mysteries by C.L. Grace are a good example. Not the best writing ever or even necessarily the best mysteries, though the plots were always interesting. But I still devoured the series because I wanted to know what happened to Kathryn and Colum (and had to know if they ever got together). I still recommend those books, if you're fortunate and find them in your library or buy them used, because the main characters are delightful. And I was invested in their story beginning to end.

To some extent, I feel like creating an emotional connection between reader and character is more important than technical execution. It's all important, of course, but I'm quicker to forgive an author for some technical issues if I'm emotionally invested in the characters. I'll read on just to find out what happens to them, regardless of the plot or actual writing. Maybe that's just me, but the more I pay attention to what readers say, it's hitting me how important it is to infuse heart into your stories instead of just technical know-how.

What novel(s) would you cite as a great example for emotional investment? What book(s) failed in that department despite other things that were right? And, to top it off, how do you feel about the importance of emotional connections and characters?