Character outside of plot

I think plot is something that springs from character, and that the two are pretty much inseparable. So perhaps this isn't the most accurate title. But there's something I see occasionally (probably because I'm guilty of the same thing), and that is when a main character is not a complete, breathing person but an empty set of eyes to see the plot by. And this ties into how to make your reader identify with the character and feeeeel.

We want to make the main character sympathetic, right? One way to do that is to show them being nice to someone weaker than themselves. Another way is to show how other characters are worse than the MC. But it's not enough to feel sorry for your MC. Pity isn't the same thing as love, you know. Nor is an empty set of eyes. It's hard to love a character who just records events without being personally involved. The big question you have to settle for the reader first of all is, why would they want to hang around this character for 200+ pages? And to help answer that, you need to show who this character is. So imagine your character outside of the plot of this particular story. Who are they? What are they like when the bullies AREN'T around? What do they dream of, what do they want, what are their aspirations for when things go right? What makes them the most happy, the most relaxed, the most themselves? How are they good? You need to know (and show) those things so that when the plot happens, we have someone to love and cheer for. Of course you aren't going to want to explain all this before the plot starts--you need action and choices right up front, too. But it's important to weave in this sense of character early on so that you give your reader someone--a real someone--to cheer for.