Continuity mistake: In the scene in the garage near the beginning of the episode where the characters are gathering supplies, the sun is on them in one shot. In the reverse shot, they are dark and the sun is no longer shining into the garage. Then back to them, it is again.
Continuity mistake: The Wolf is shown to have filthy teeth but when Carol confronts Morgon in The Cell, his teeth are clean.
Knots Untie - S6-E11
Continuity mistake: When the bus gets stuck in the mud, the team leaves the vehicle. However, their shoes/boots are already covered in mud despite having not left the bus yet. (00:17:50)
Continuity mistake: When the sodas are retrieved from the cool box there are 6 cans, but when the angle changes there are only 4.
Answer: Walkers are attracted to noise, they can tell who's dead and who isn't dead, in S1 when Rick and Glenn cover themselves in walkers' guts they're able to get far by walking through the herd of walkers because they smell like they're dead, but as soon as the guts get washed off by the rain the walkers immediately attack them, if you draw attention to yourself they will attack you which we've seen that many times throughout the series that it's not always successful. Whether you're covered in guts hiding under dead corpses or under a car.