Parking is a joke...
The current methods of enforcing parking are a complete joke...
Where they make you pay in advance is always a scam, you don't always know how long you're likely to be there so you end up paying more than you need or getting fined if you are unexpectedly delayed. Coming back to the car to top up the ticket wastes your time, and unless you time it perfectly you pay twice for the overlap time.
Parking wardens are not there to enforce the rules, they are there to make money and they have quotas of tickets to fill. If they see you about to park, they won't jump out and tell you not to park there, they will wait until you leave the car and then ticket you. It is in their interest for people to break the rules and get fined, because if noone broke the rules the wardens would get fired for doing their supposed job too effectively.
Also, parking tickets have become a cost of doing business for countless delivery companies... There are thousands of businesses that require deliveries of various goods, and yet there is nowhere nearby for the delivery vehicle to park.
Just a few days ago i saw a pub that has stood for hundreds of years having large barrels and crates delivered... The truck parked right outside and got a ticket almost immediately - like the warden knows when the pub is scheduled to get a delivery and waits for it. There is nowhere else for the driver to park, there is a public car park nearby but it has a height restriction on the entrance and would require transporting the heavy deliveries across the road - likely to cause more obstruction than the truck.