1) Costs. A car costs about $35k - $40k new. IF you qualify for the rebate, you get that back (it is not automatic, you have to have certain tax levels). So they are not cheap.
2) Most people only have one car per adult (over 18). This is so they can go to work, etc. Most people need this car so they can do all tasks needed (the jack of all trades sort of thing) which includes road trips to grandma's 2 states over. If you are married it becomes much easier to have a pet car that has limited
3) Range. Cars need to get you from point A to B, and range is key. If you don't work some place where you can recharge, you cannot top the tank at work. They you are stuck with the range you have. If you live in a place with cold weather winters, your range decreases by as much as 15%. Your 100 mile range now is 85 (not including the heater having to be run) just from the physics of the battery.
4) People have different needs on different days. I work as a consultant, and a college professor. When I consult, I drive 20 miles a day to work or so. When I teach, I drive 40 miles one way to teach. I cannot consult and teach on the same day with most modern electric cars (outside the volt or tesla). I would have to drive to work, drive home, pick up my other car, and drive to teach. Not going to happen.
5) They are picking shitty bodies/designs. I don't drive a chevy cruze, or a sedan at all. I drive a crossover due to its ride height and utility and size (I am a big dude). I don't fit in tiny sedan cars. If they put the guts of volt in a crossover, it would be a hit. GM sells more trucks and SUV/crossovers than they do cars. Same with Ford. Same with Chrysler. It is not what the masses want. I would love to own a volt. I have been following it since 2007 when it was first announced. However when I first sat in it after waiting 4 years, I don't fit. Too small of a driver cockpit.
6) People are uneducated about what a car can do. Many people just don't know how to deal with the simple way that things work as they don't become educated about the cars they purchase. You cannot believe the comments I have seen on several EV boards about cars.
7) People are stuck in their ways. Gas is good and electric is bad. I have an electric but have to rent a car to drive to grandma's two states over for christmas. Okay. But it is not my vehicle
8) Cars are not available everywhere. I don't live in California. I live in Indiana. I don't get a Kia Soul EV. I don't get a Toyota Rav4 EV. These are only sold in California for CARB compliance reasons. The manufacturers don't want to have to deal with them so they allow those cars to be sold out of that state.