@feha
It is because you have seen it 50+ times already. The weak guy who by no means should win somehow manages to scrape by a victory, only to faint right after.
I have seen this enough time where I think authors are now just using it as a convenient location changer and chapter ender. Where they dont really care about the immediate aftermath, and usually end things by having the "enemy"/conflict opponent (this time it is the knight) just leave a message, or go far away on a journey to somewhere forever out of the main plot, only to appear as a potentially reoccurring side character.