Originally Posted by
grain
no, i not 100% on this, but i believe it is when they give a boarding pass to someone thats standing by and they already have a full plane of 137, thus they have to spin around, and come back off.
This is the correct answer. A Spinner normally is caused by a thru count error, like people not staying in their place or trying to fly the next leg for free. 99.9% of the time in that case the person is caught. Normally it is just a case of too many standbys being place on board. Two standbys cleared and between them a confirmed passenger shows up and gets on the plane. The standby is pulled.
It is called a spinner because the person is normally just spinning around looking for any open seats. It can be pretty embarrassing, knowing everyone is waiting for you to sit down so they can get on their way.