Yes, most likely buyers. Some buyers usually will lie about not receiving their items, but there are some loop holes that end up indicating that the buyer is lying. Besides, both parties (seller and Poshmark or any other online site) investigate this claim closely and go as far as involving the mail carrier and also file a legal claim for high dollar items.

All packages shipped are sent via USPS Priority mail with tracking. I've shipped hundreds of packages on various sites and have never had a problem with an item being marked as "delivered". There is very little room to lie about not receiving an item if it has been marked delivered. If you sent something out and the buyer is claiming they didn't receive it, ask them to check with family members or possibly a neighbor that would have picked it up for safe keeping. With any package, there is a chance of it being stolen.
Poshmark automatically releases funds to the seller 3 days after a package has been marked delivered by USPS if the buyer doesn't confirm they have received an item. I'm sure there are scam artists that will try to say they didn't receive something that they received but I don't believe they will get very far because of all packages being shipped with a label straight from Posh with tracking.

Hi Nancy F... the Postmark pkg. Is tracked while in transit. You don't physically sign for it when u receive it ( like FedEx)so I don't know how it can be proven either way... hope this helped.

As like any other site you take that gamble online they will investigate it if you put in a complaint but there is never guaranteed either way that they can side with you for the sender if the tracking number states the package arrived to you you have a lot of honest ones and I'm sure you'll have a few bad ones sometimes looking at their profile are they considered a top-rated seller or have a high rating can give you an idea who you may trust some people leave complaints and compliments on their page as well

Poshmark has a grantee that if you don't get your item or its not what the description tells you you get your money back and the buyer dont get paid til u receive your item andrarte it thinking about joining use BVLAS code to get $5