On: TfL's simple pop-up message led to a significant d...

[amenhotep]

Might be an economies of scale thing? If you're offering paper tickets you need the machines for them, you need to pay to maintain them, that is a minimum cost that you can't really decrease as usage drops. If one machine is servicing a million tickets, the per ticket cost is negligible; if usage drops and you're trying to split the cost among a hundred tickets, it's going to look extortionate.

Cf the guns on the Zumwalt class destroyers.

[bobthepanda → amenhotep]

Most of the cost of traditional methods is the needs of securing collection.

Ticket machines take cash and that cash needs to be securely transported. Similarly a paper ticket needs to be collected for possible auditing later.

Contactless is much easier since all the records are digital and the user carries their card with them.