"Once it's been in an accident..."

"Bike helmets. Once it’s been in an accident or even just dropped, the foam is compressed and won’t protect you as much."

beetlereads

This is very true! Do not ever use a helmet that's already sustained an accident. It could be as bad as not wearing one at all.

"Fire chief in my town once said a ladder truck. He wouldn’t ask anyone to climb a used ladder. A used tanker or ambulance maybe."

Ok-cantaloupe7160

Don't those things have maintenance and inspection protocols in place? I would certainly hope so.

"Hard drives and flash memory..."

"Any sort of computer storage."

"Hard drives and flash memory used in solid state drives and flash drives wears down over time. The more you read and write to it, the more it wears down. If you buy used, you don't know what that storage was used for, how often, or how heavily. It could last you years to come or die the next day."

Batcastle3

Considering the lifetime of SSDs, it's kinda okay. There is almost no way to break one, and the cell life time is good, and controllers help protecting them from wear leveling.

For HDDs though, buying used drives is a bad idea.

"It's one thing..."

"Fabric furniture. It’s one thing to by your friends couch, but you have no idea what was going on with that sofa sitting in goodwill."

PMme

Bedbugs are terrifying. Trust me, you never want to deal with them.

"Though really..."

"Wicker furniture. Though really, you shouldn't buy that type of furniture at all. It's the perfect nesting space for bugs."

[deleted]

See?! What did I tell you?! Don't do it!

"You can't use them..."

"Oh, and baby car seats. You can't use them after a car accident and buying secondhand means you can't always verify that it hasn't been in one."

[deleted]

I would certainly hope that people aren't still using them after accidents. That's just asking for trouble.

"Once they've been..."

"Shoes, especially for kids. Once they've been worn in to conform with someone else's foot, you don't want your kids putting their growing feet in there to get reshaped."

i_know_tofu

Also... gross. Just gross.

Get your kids feet measured regularly and listen to your kids if they tell you that their shoes are too tight of they hurt.

"They're expensive..."

"Children's car seats. They're expensive but there's no guarantee what condition they are in second hand, particularly if they've been through an accident already."

[deleted]

Parents, take note! You'll definitely thank yourselves later.

"Climbing rope. You can't tell how many falls its had or how old it is, and it's literally your life line when you're rock climbing."

JudeoCrustacean

Very important! People die in climbing accidents each year – don't be one of them.

"It's actually not healthy..."

"Shoes. It’s actually not healthy to walk in some other person's shoes. It has an impact on your whole body and can cause severe different pains in your body."

pulpriot

You don't want to have issues with your feet in later life! Again, you'll be thankful you listened to this advice.

Some other things I'd add off the top of my head: Mattresses, power supplies, oh, and... this should go without saying, but underwear,

Yes, underwear. The human race pains me.

Have some recommendations of your own? Tell us more in the comments below!