Stories are about people. I cannot imagine a story with no people in it. They are the life's blood of a work. If you like the people, you will be interested in what happens to them. If you don't, then you won't.
You do not always have to agree with a character to like them. That is where villains come in: those people with fatal flaws which provide dissonance to the assonance of the heroes. And just as in music, the story flows from the interaction of these elements. For there must be a resolution.
If the ending is predictable, it feels as if you are listening to a song that sounds like so many others. Then, there are the resolutions which are not satisfying. And they are like musical arrangements that leave much to be desired. But a good ending, is like the song that you cannot help but hear over and over again in your head.
Just as music can be flat and uninspiring, so characters can be shallow and undeveloped. The best characters are those you come to know as people: they think and move and feel. They will not always agree with the author. Rather, they will have their own opinions.
These unruly creations give life to the work. For they draw attention to themselves: some providing the melody, while others the harmony of the tale. And when they are finished, you sit back and let out a contented sigh. For you have just experienced a true symphony of dark and light; of death and life. And the mighty crescendo stays with you for days, as the song of your soul.