The shorter I am, the bigger I am. What am I?

Why this works

This riddle plays with the double meaning of the word "shorter." When we say someone has a "short temper," it means they become angry more easily and intensely, making their temper seem "bigger" in terms of emotional impact. Thus, the shorter the duration of their patience or tolerance, the more significant the outburst of anger feels—hence, the clever twist that a shorter temper is actually a bigger one in terms of its effect!