Sensors on the gate stop someone putting in another ticket until the first
has cleared the sensor. The non ticket person pushes up against the gates
and this clears the sensor (didnt take them long to work it out)....so the
next ticket is able to go in. Sometimes the non payer reaches around and
takes the good ticket...leaving the second person saying "my ticket is lost
in the machine". The gates actually open when you take the ticket out, not
put it in.
The answer is not to take out your ticket until the person in front is gone.
But in the rush......this is a hard one to remember.

"Colum Mylod" wrote in message
...
Having seen this several times a week, why were ticket gates so
designed so that if someone bunged in a paper ticket which the gate
rejected Seek Assistance, it is possible and even probable that a
too-fast person behind can insert their ticket which lets the rejected
person through and traps the eager beaver? Every time I see this, the
one left behind wails to staff, they wave their supposedly valid
ticket and are let in, so I guess the lucky one in front has to find
another victim at exit, vault the gate, use an unguarded station.

Is it not possible to "eject" the failed person (as it were) before
allowing a ticket to be inserted after a rejected one?
--
New anti-spam address cmylod at despammed dot com