The hindrances are the bricks of which the dam is built. As mindfulness dissolves the bricks, holes are punched in the dam and compassion and sympathetic joy come flooding forward. As meditative mindfulness develops, your whole experience of life changes. Your experience of being alive, the very sensation of being conscious, becomes lucid and precise, no longer just an unnoticed background for your preoccupations. It becomes a thing consistently perceived.
Nothing is glossed over or taken for granted, no experiences labeled as merely 'ordinary'.
Everything looks bright and special. You refrain from categorizing your experiences into mental pigeonholes. Descriptions and interpretations are chucked aside and each moment of time is allowed to speak for itself. You actually listen to what it has to say, and you listen as if it were being heard for the very first time. When your meditation becomes really powerful, it also becomes constant.