Sia has a pretty pervasive theme in her tracks:
Resilience.
This song is no exception.
In fact, the lyrics are quite similar to another song by Sia (Bang My Head), which was the first post in this "Music Motivation" series.
 Lyrics you might like: 
And I won't let you keep me down
I'll keep gettin' up when I hit the ground
Oh, never give up,
No, never give up, no, no
Here's to the fortitude to never give up!