You buy a six‑foot stepladder from a big box store. The box shows a happy man changing a lightbulb. Inside, the ladder looks solid. But there is no sticker, no stamped warning, no instruction sheet. You set it up on a slightly uneven patio, climb to the top step, reach sideways, and the ladder tips. You fall, break your wrist, and spend weeks in physical therapy. Who is responsible? Under product liability law, the answer often starts with what the manufacturer did not tell you.

Manufacturers have a legal duty to warn consumers about dangers that are not obvious. This duty is separate from the duty to design a safe product or to manufacture it without defects. Even a perfectly built ladder can become unreasonably dangerous if the manufacturer fails to include clear, prominent warnings about how to use it safely and what not to do. The law calls this a “failure to warn” claim, and it is one of the most common types of product liability cases.

The key question is whether the danger was “open and obvious.” If a risk is one that any reasonable person would see without being told, the manufacturer generally does not have to warn about it. For example, a knife is sharp. Everybody knows that. A warning label on a knife handle saying “this knife can cut you” would be pointless. But many product hazards are not obvious. Consumers do not automatically know the maximum weight a ladder can hold, that using the top step as a seat increases tip‑over risk, or that setting the ladder on soft ground makes it unstable. Those are hidden dangers that require a warning.

When a warning is missing or inadequate, the manufacturer can be held liable for injuries that result. Courts look at several factors. Was the danger foreseeable? A ladder company knows that people will sometimes stand on the top cap or reach too far to the side. Those are predictable misuses. The warning must address those foreseeable misuses, not just the intended use. Was the warning itself clear? A tiny gray sticker hidden in a crease of the leg, or a paragraph of tiny type buried in a multi‑page manual, does not cut it. The warning must be conspicuous, use plain language, and include symbols when appropriate. It must also be durable. If the warning rubs off after a week of use, the manufacturer may still be liable.

The classic example of failure to warn involves chemicals, but the same logic applies to mechanical products like ladders, lawn mowers, power tools, and children’s furniture. Consider a child’s dresser that can tip over if a child climbs on an open drawer. The danger is not obvious to a parent who has never heard of tip‑over accidents. A manufacturer must warn that the dresser must be anchored to the wall. Without that warning, and without including an anchoring kit, the company faces liability if a child is crushed.

Bad warnings can be just as dangerous as missing warnings. A warning that says “do not use on uneven surfaces” is vague. Uneven how? A warning that says “do not exceed 250 pounds” does not explain that the weight limit applies to the total load including tools and the user’s body, and that dynamic forces from reaching or jumping can reduce that limit. Warnings that are contradictory, erased by competing labels, or buried under other text fail the legal test of adequacy.

In a lawsuit, the injured person must prove that the lack of a proper warning caused the injury. That means showing that if the warning had been present and clear, the person would have read it and acted differently. This is known as the “heeding presumption.” Courts often assume that if a proper warning had been given, the user would have followed it. The manufacturer can try to rebut this by showing the user was drunk, ignored other visible warnings, or was acting recklessly. But in most cases, the presumption works in favor of the injured party.

The consequences for manufacturers can be severe. Compensatory damages cover medical bills, lost wages, and pain and suffering. Punitive damages are possible if the missing warning was a result of reckless disregard for safety. For instance, if the company knew that consumers were falling from ladders because of a lack of weight‑limit markings but decided to save money by not adding stickers, a jury may award extra damages to punish the company and deter others.

From a practical standpoint, manufacturers should treat warnings as a critical part of product design. It is not enough to build a safe ladder. You must also tell people how to keep themselves safe. That means testing warnings with real users, making them visible at the point of use, and updating them as new hazards become known. For consumers, the lesson is simple. If you are injured using a product that had no warning about the exact risk that hurt you, or if the warning was confusing or hidden, you may have a strong legal case. The law does not expect you to guess at hidden dangers. It expects manufacturers to tell you about them.