By all rights, the zombie shouldn't be as big of a threat as it is. After all, zombies are slow, dumb, easily tricked, and can be easily evaded with proper planning. In addition, fighting them off isn't usually a huge problem when they are by themselves or in small numbers, allowing characters to take out wave after wave before the climax. This depiction has lead to several stories where their weaknesses are played up for comedic value, making them appear even less dangerous than they have appeared before. This aspect of the zombie is so often played up to such an extreme that people are often taken aback when a zombie gets a lucky shot in and infects or kills another character. After all, the characters seemed to be doing ok before. Yeah, they may have proven a somewhat decent threat, but otherwise they didn't seem to have what it took to beat the charming characters on screen. Yet each and every zombie does in fact pose a threat due to one powerful weapon they all have: the power of the bite.
While each zombie is individually weak, all it takes is for one zombie to bite a victim and that victim will join their ranks sooner or later. This bite is so powerful that their entire power set seems to revolve around it. For zombies are strong enough to break through most things, immune to pain and able to keep chomping away even if all that's left is a disembodied head. For it doesn't matter if one or two or a hundred zombies fall, the instant they nibble on your flesh, your fate is sealed. Oftentimes it is through this tenacity and this single-minded purpose that most characters ultimately fall to these monsters. For as skilled, smart, and strong as you are, you can't fight forever...but the zombies sure can. Even the most powerful and smartest are not immune to bad luck, fatigue, or the occasional mistake every once in awhile. It's part of being human. However, when a horde of zombies is on your tail, that moment makes all the difference. In that instant your luck fails, you flag behind, or make that mistake you will fall...but not always at the mouths of the zombie horde. For as the movie Zombieland shows, when zombies take over the world, the ultimate goal isn't to beat the zombies, but to survive as long as possible. Through the main character's discussion of the various rules he has on keeping alive in Zombieland, we become aware that the entire world is out to get you(See Below).
The zombies do not care if you die by their jaws or through other means. For when you face the jaws of a Zombie, you face off against the inevitability of your death one way or another.
