I think" all the lost & found" refers to the experiences you gain from being really alive. The more involved you are with your life, the experience you gain and therefore you lose and find more sometimes than others.
So perhaps this person was not yet involved with their life - but the lyricist obviously holds them in a regard which shows the potential to be truely better, and burn brightly if only the effort is made.
However I think a certain amount of respect is being given to the character just for existing at all by the tone of the song.
I think" all the lost & found" refers to the experiences you gain from being really alive. The more involved you are with your life, the experience you gain and therefore you lose and find more sometimes than others. So perhaps this person was not yet involved with their life - but the lyricist obviously holds them in a regard which shows the potential to be truely better, and burn brightly if only the effort is made. However I think a certain amount of respect is being given to the character just for existing at all by the tone of the song.