My answer is this.
1. Bluetooth headphones need to be charged after they are bought.
2. Because the Bluetooth headset is not fully charged when it leaves the factory, this can ensure that the battery does not change, so we need to fully charge the battery after we get it. After full charge, the memory function of the battery is activated, which can ensure that our battery has a longer life, so I think that the Bluetooth headset needs to be charged after buying.