It's the upfront costs that are an issue currently, as many...

It's the upfront costs that are an issue currently, as many simply can't afford them , life of vehicle savings will not be high in the thoughts of the average Joe six pack . At some stage there will be also a road user tax of some type, that will become a another running cost also any incentives will fade away.
Resale prices are also a big unknown given the speed battery technology changes, a fuel tank has always been a fuel tank and the contents haven't changed, the battery and the process of charging will continuously evolve leaving earlier systems obsolete relatively quickly.

However the trend is very appearant , the issue around upfront costs will be resolved and there is no doubt the running costs will be lower whatever gets thrown at it but will take some time..

Cheers Whisky