BMW’s and Tesla’s premium electric cars both failed to earn the Insurance Institute for Highway Safety’s (IIHS) Top Safety Pick rating during recent crash tests, both of them near-misses the vehicle testing agency said come down to details.

Meanwhile, 2017 versions of plug-in hybrids from Chevrolet – the Volt – and Toyota – the Prius Prime – both painted preferable pictures of possible protection and earned the Top Safety Pick+ rating, the score the IIHS gives to cars that represent the safest models on the road. It gave special kudos to the Prius Prime for its standard suite of advanced safety features.

The cars that just barely missed that rating were the compact BMW i3 and the full-size Tesla Model S; this latest round of crashworthiness tests was Tesla’s second crack at impressing the IIHS, while it was the first for BMW’s little electric hatchback.

Tesla missed the mark due to an ‘acceptable’ rating in the IIHS’ small overlap frontal test, and ‘marginal’ scores for its headlights and difficult-to-use child seat anchors. IIHS engineers noted a high likelihood of head injury to the driver because of a seatbelt that allowed the test dummy’s torso to move too far forward on impact and its head to strike the steering wheel through the airbag.

The challenging small-overlap test runs about a quarter of the width of a car’s front end into a fixed barrier, avoiding its main crush-zone structures, which the IIHS says tend to be concentrated in the middle 50 percent of the car.

Tesla says a production change made in January was conceived to address the head contact problem, a claim the IIHS will test when it gets its hands on an example of the updated car.

Also keeping the Model S out of the winner’s circle was inadequate visibility in both low- and high-beam tests. And the IIHS has yet to rate the Model S’ automatic emergency braking system, which the institute notes is standard in all models but whose functionality is unavailable in all cars because Tesla hasn’t “yet activated the software for all vehicles.”

In testing the BMW i3, the IIHS noted the car was the only 2017 small car that doesn’t get the institute’s “good” overall rating. BMW can blame that on seats that don’t provide adequate protection from neck injuries in a rear-end crash; plus the i3’s headlights get only an ‘acceptable’ rating.

Otherwise, the i3 does well, getting ‘good’ rankings in all other crash tests, and it can be optioned with a front crash prevention system that scores three points out of a possible six.

IIHS says it will test another avant-garde electric, the Chevrolet Bolt, later this year.