The racing adrenaline that pumps your heart while you're sweating bullets during that decisive moment. Your spine tingles, you've acquired goosebumps, and your gaze is immersed towards the screen and it's only been three episodes. An hour of your time and you've become entrapped in Hajime no Ippo. I can personally proclaimed that two of my buddies who can't stand anime and call it a waste of time watched Hajime no Ippo from beginning to end in the matter of a week.
Hajime no Ippo can turn people into anime craving fanatics in need of more face pounding action. Basically, it can change your religion. Excuse the overexaggerated text.