There are some things that people generally prefer to buy new rather than used due to hygiene, safety, or reliability concerns. Here are some examples:

1. Mattresses: Many people prefer to buy new mattresses due to hygiene concerns. Used mattresses may contain dust mites, bed bugs, or other allergens that could trigger allergies or other health issues.
2. Car seats: Used car seats may have been involved in accidents or may have expired, which could compromise their safety. It’s generally recommended to buy new car seats to ensure that they meet the latest safety standards.
3. Underwear and swimwear: For hygiene reasons, most people prefer to buy new underwear and swimwear rather than used items.
4. Bike helmets: Used bike helmets may have been damaged in a crash or may have expired, which could reduce their effectiveness in protecting the wearer. It’s generally recommended to buy new bike helmets for safety reasons.
5. Electronics: While it’s possible to buy used electronics, there is a risk that they may be defective or may not work properly. In addition, new electronics typically come with a warranty or return policy, which provides additional protection and peace of mind for the buyer.