There are many predictable situations within an unpredictable world..
(Story time)
You're in the zombie apocalypse, and as you're traversing the land with your grumbling belly, and sun-chapped lips, you happen upon a supermarket. It looks almost new. It briefly reminds you of simpler times that you took for granted. You crouch down, and spend the next several minutes cautiously looking all around you. Thankfully, the area all round you is flat with no trees giving you a visible sight-line for miles, not a single zombie, the only thing you ever saw moving was a dirty plastic cup taking a quiet, rolling ride across the asphalt on a gentle breeze. You think to yourself, "Well, it's now or never, the coast is clear outside, at least" You look all around once last time, checking behind you as well and then as you face the super-market again - a horde of zombies is there. "How is this possible!!" you ask out loud. "There's absolutely no way that any zombie could have traversed that parking lot during the two seconds I turned around."
Of course even in a fictional situation such as the zombie apocalypse - a shambling zombie has predictability. You can predict where they can possibly be or can't possibly be based on their movement speed.