Most problems with eBay standard envelope are self inflicted
eBay standard envelope is a low cost way of shipping items sold on eBay that fit in a regular letter envelope and weigh three ounces or less. The items eligible for this shipping method include the following:
- Patches
- Stickers & Decals
- Greeting Cards
- Seeds
- Trading Cards
- Coins & Currency
- Postcards
- Stamps
What makes this method work for eBay is that unlike a normal envelope sent through the United States Postal Service, items shipped this way come with tracking.
Sports card collectors can be... a little weird
I've sent and received a lot of trading cards using it. Both sports cards and Pokémon cards. It's because of my personal experience that I can say people sending and receiving sports cards have real difficulty with it.
Most problems with eBay standard envelope are self inflected. Sports card sellers either don't understand the rules, don't care about the rules, or they make up their own rules. All envelopes shipped using eBay standard envelope must go through an automated mail sorter. If they don't, there will be no tracking.
The type of barcode on an eBay standard envelope label can only be scanned when it goes through an automatic sorting machine. It's called the Intelligent Mail barcode. Humans cannot scan it. That's by design. An envelope will not have tracking if it cannot go through an automated sorter.
The envelope needs to be flexible. Too many envelopes sent using eBay standard envelopes are not flexible. Too many sports card sellers send cards in chipboard photo mailers with cardboard inside.
An example of eBay standard envelope done wrong
Here's a good example of someone not understanding how to properly package something using eBay standard envelope. This envelope was returned to the sender because the envelope could not go through the automatic mail sorter. It was either too thick (< .25 inch) or not flexible. It was probably a combination of the two.
In my opinion, even a top loader card holder is too much. That said, when I send sports cards using this method, I send them with a top loader. I do it because that's what people expect. If I sent sports cards in a semi-rigid card holder like I do with Pokémon cards, the card would arrive in perfect condition, but the chances the buyer would leave negative feedback are high.
In conclusion
I buy single Pokémon cards all the time from Japan. I've never recieved a Pokémon card from Japan in a top loader. I've also never received a Pokémon card from Japan that was damaged.