RECEIVED A PARKING CHARGE NOTICE FOR ENTERING INCORRECT CAR REGISTRATION PLATE DETAILS ?   THEN READ ON.........

The purpose of this requirement along with the instruction to place the ticket face up on the dashboard was surely to stop the mischief of the ticket being passed onto another motorist to use , who of course could then avoid buying one. Car park attendants could easily check and match the registration details on the ticket to the car in question.
With camera-automated car parks, the operators  can easily check the camera records of the car registration plate with those entered into the ticket machine to make an instant match. Even if the details are not exactly matching, it is still easy to establish that the car entering the car park was the one for which a ticket was purchased, such as when the letter "O " is entered instead of the number " 0 ". This advanced technology of course enables companies to dispense with car park attendants , which reduces their operational costs considerably.
Despite The Beavis ruling , two recent County Court judges ruled in favour of the defendants when both had entered in error the registration details of their other car. See Excel Parking v Burgess (2017) and Excel Parking v Koselka (2017). In each  case both argued they had paid the correct money , had not overstayed , and the errors were innocent mistakes with no deceit intended. The company had not suffered any financial loss whatsoever. 

Finally I would like to revisit the law on offer and acceptance regarding ticket machines as this might provide a possible line of defence against claims that parking tickets are invalid if incorrect registration plate details are entered into the ticket machine.
In Thornton v. Shoe Lane Parking (1971) the Court of Appeal held that the ticket machine constituted the offer. The acceptance of the offer with all its terms took place when money was put into the machine. The ticket was dispersed after the acceptance took place.
In the car park scenario terms of the offer are meant to be accepted unconditionally as soon as payment is made.  However by entering different or incomplete details , the purported acceptance has varied this particular term with regards to providing the correct registration plate details . This makes the acceptance conditional which by legal definition turns it into a counter-offer. With the boot on the other foot , acceptance of the counter-offer takes place when the money is taken by the machine ( with no refund possible ). The issue of the ticket with the keyed in registration details printed on the front  is therefore valid , with all but one of the car park's terms and conditions applying.  Any PCN issued is  by any logical conclusion unfounded and unenforceable.