We made a little money by switching long distance carriers.
In the beginning, we could switch freely any time. The tele-salesman
would call us any time to offer us money. The logistics was
somewhat inconvenient. We had to pay your $5 switching fee first.
Then after a month or two, we saw our reimbursment and free minutes
in the bill.
The profits really came to us when the competition became so fierce
that the carriers started to send us money directly. By cashing
the checks, we agree to six-month terms. As long as we did not make
many calls, the checks were pure profit.
One day, the tele-sales lady told us that our six-month term was
up. It was time to switch! "Not to worry, if you really liked
AT&T, my friend will switch you back six months later. That way
you always receive free money twice a year." And surely every
six months, we got phone calls asking us to switch and switch back.
The sales people continued to hand out checks to us. They got paid
commission. We got cash. None of us generated significant revenue
for the carriers. But we continued to take their money. They had
to find other ways to cut cost and make money. They resorted to
ripping us off.