"Never underestimate me! I don't quit and I don't run," from Chapter 43, is a testament to his unwavering self-belief and determination. Despite being constantly underestimated and mocked for his perceived lack of talent, Naruto's stubbornness and guts to never give up when challenged go on to define his character. It's this unwavering self-belief that pushes him beyond his limits time and time again throughout his story. It is a call to remind us to believe in your inner beast. To get up after every failure, to push through every challenge, and prove you are that guy.