Where are you getting this from? A MINI SE is basically the same price as a gas powered MINI (without any rebates). A Tesla is basically the same price as the equivalent BMW or Benz high end sedan (and Tesla doesn't qualify for federal rebates anymore, BTW), and those big BMWs and Benz sedans depreciate like crazy. So does any other car (except this year, I guess). Then add in the fact that you don't need to change the oil (have you priced a dealer oil change for a high end Euro car lately? it's hundreds of dollars). That also adds up over 10 years.
Jim, I didn't make up the price differences. It's what's out there, even as Les says.
Also, keep in mind there are differences in the quality of workmanship. Better leather, better sound, better-integrated console not some cheap iPad with no control knobs to reduce fiddling while you're driving. To me, a Tesla 3 looks like a cheap Toyota Corolla that costs many thousands less. Because of the extra cost of the batteries, they scrimp on the quality of other things to keep the price competitive.
Of course, as the price of batteries continues to decrease, that will change. Let competition get going and I think things will get better, both pricing and quality. It's still too new. It's like digital cameras when they first came out. Interesting concept, exciting to play with, but film was still better. That's changed. Well, I suspect similar things will happen with EVs.