In uk.transport.london Robert wrote:
I cannot for the life of me see what the advantages are, for the
customer, of an electronic form of payment over cash for small amounts.

Cash is well developed, the bugs have been ironed out of it and it's
easy to see your current balance.

Being cynical, I think you'll find that's a misfeature. Plastic has the
'advantage' (for the retailer) that the customer cannot easily see their
balance and is tempted to spend more. Hence the reason why cash is on the
rise again, as people are trying to keep more control over their finances.

Theo