Guys,
This goes on all of the time like a wash-rinse-repeat cycle. Your freight space is marketed by the sales force. They compete and the customers play the shippers off of each other. I was with the Purple back in the early 90s in ground ops and saw the gyration then. I have done supplemental flying work for Brown, DHL and Bax. They all compete. There will always be churn.
We just have to do our best to keep the boxes moving. The sales force and large shippers play the games!
Former walking wheel chock.