Total Output Errors
The sum of all errors that prevented the final transmission of datagrams out of the interface being examined.
You should expect to see those types of errors, especially if the airspace is packed with other 802.11 devices or you have other interference issues.
One thing to remember is that the 802.11 standard specifies a Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) transmit-recieve environment. Therefore, all 802.11 are half-duplex/simplex in nature.
Billy