I've just noticed the parallel between Dementus' "Where are you going, so full of hope? There is no hope!" and Max's "Hope is a mistake; if you can't fix what's broken, you'll go insane".
Furiosa was likely told many more times that hope was pointless, that nothing could save her or others around her, yet it's literally her hope, the sheer power of it, that ignites the entire story. Her hope to return to her clan, to find the Green Place, to save the Wives. For most of her life, all she had — and could have — was hope.