Every one hates to sleep on a previously owned mattress, especially when you have paid a full price. But every one is a potential "producer" of a returned mattress.
Self-contradictory?
Yes, but it's also understandable.
As consumers, we have learned that we won't always pick the perfect mattress on the first try. That's why most people try mattresses until they find one that suits them. This inevitably leads to returns. Because some other person has slept on them, such mattresses are as new as Ancient Egypt. But we can't exactly classify them as old either, as they have only been used for a short while. Normally, they are neither undamaged nor uncontaminated.
That said, no one wants to sleep on a pre-owned mattress.
All above begs the questions:

The answers are actually what nobody tells you about buying a mattress.
Keep reading and find out.

The dilemma

To answer the questions posed above, you need to know the motivations of both buyers and sellers.
After all, a deal is the result of a compromise between the two.
What buyers want?
Buyers want the best product for the lowest possible price.
If the product is not to their liking, they return it expecting their money back. In most cases, the buyer does not assume the cost of shipping.
We should also keep in mind that buyers are not willing to buy a previously owned mattress.
That often compels the seller to donate returned mattresses.
So if the only way the buyer can get a refund is to donate the mattress, (s)he will want a convenient and stress-free donation process.
(Want to donate? Find a charity near you.)

What sellers want?

On the one hand, sellers would like to set a price that will make them as much profit as possible.
On the other hand, they need to set a price that will attract their target consumers.
In order to gain a price advantage, the seller's product must be cheaper than that of the competition.
This means the book on minimizing costs is required reading for all sellers. One chapters of the book is about minimizing the cost of mattress returns.
Generally speaking, the rate of mattress returns is stable. So how sellers deal with returns determines how much or how little these returns eat into their profits.

How returned mattresses are dealt with is a hidden side of the mattress business which is seldom revealed.

What we know is that each mattress brand has its own policy when it comes to handling returns.

Mainly three ways are used for mattress returns

 1. Abandoning the mattress

This involves either destroying the mattress or donating it.
Abandoning mattresses can put a strain on the finances of a business, because the original cost and shipping fee of a returned mattress is never recovered.
Besides, destroying(melting or burning) the mattress is a waste of materials that could otherwise be reused.
On the bright side, donating the returns helps both the needy and the environment.

However, consumers may find the process of donating a mattress in order to get a refund to be a hassle.
Presently, a number of online mattress brands ask buyers to donate by themselves.
According to an article by a New York Times journalist, most of returned mattresses are donated to charity but donating is not easy to do.
Another bad news is that:
Mattress sellers factor the cost of donated mattresses into the sale price.

2. Repackaging and resale of returned mattresses

Shipping returned mattresses back for resale is a far cheaper alternative to abandoning a mattress.
In that way, the only cost incurred is the shipping cost.
But can returned mattresses be sold?
It is not always allowed. Some states forbid the resale of returned mattresses.
The reason is that mattresses are personal items that come into direct contact with skin, hair and body fluids, all of which adhere to the mattress.
In addition, germs, skin diseases, bedbug and bedbug eggs can easily spread when returned mattresses are resold.
However, because reselling returns is cheaper than abandoning them, mattress resellers offer temptingly low prices on returned mattresses.
Sellers take advantage of the lowered costs to realize a decent amount of sales in low-end markets.
The lowered prices and convenient return policy attract many consumers.
When buying returned mattresses, what those consumers may not know is the sometimes filthy back-story of their 'new' mattress.
If only they would read this article!
For the sake of their health, they would think twice before buying that nice-looking mattress for a steal.

3. Rebuilding and resale of returned mattresses

Rebuilding is a compromise between abandoning and reselling returned mattresses.
Some sellers simply replace the mattress protector while others replace the entire top layer. In addition, rebuilding involves sterilization.
It is more expensive than selling it directly but cheaper than abandoning.
But it is definitely a method worth trying for mattress industry.
However, there should be adequate supervision to rebuilding process by the government and the media.
Consumers can only be protected when it remains a process that is monitored closely.

Assured quality or deals that seem great

All businesses are motivated by profit, which is also the base of product quality and good service.

Based on the sale price, you can tell if a mattress is new or refurbished, or directly resold.
Brands that destroy or donate returns guarantee a product that has never been used.
However, this assurance of quality comes with a higher sale price.
In contrast, brands that resell returned mattresses offer lower sale prices. The down side is that the when you are buying a returned mattress, you are also receiving all the risks that come with it.
So if you're in the market for a mattress, you have a choice to make.
What can you live with?
An unused but slightly expensive mattress or a cheaper but possibly pre-owned mattress?
Your call.