One of the mysteries of the English language finally explained.
Unrestrained, aggressive, forceful; all-out, ‘full-throttle’.
1960s. From the plural of ball + to + the + wall. Originally with reference to the ball-shaped grips on the throttles of certain military aircraft (which were opened by being pushed forward towards the firewall), but in later use perhaps associated with ball. Perhaps compare also with one's back to the wall.
In this article we explore how to impress employers with a spot-on CV.