Slip-and-fall cases are harder to prove than you think. This is especially true in North Carolina, where not only must plaintiffs prove defendant had actual or constructive knowledge of a given hazard, they must also defend against claims of contributory negligence.
Contributory negligence is the degree to which a plaintiff shares the blame for the injury in question. In most states, the damages awarded are reduced by whatever percentage of fault a plaintiff is found to share. In North Carolina, however, a finding of just 1 percent contributory negligence means you are barred from collecting anything at all.
So for example, you might slip and fall on a gob of ketchup in the grocery store. The store knew about it and failed to clean it up in a timely manner. However, the store could argue you had a duty to notice the open and obvious hazard of bright red ketchup on the floor and take precautions to avoid it. And they could win on that theory.