I agree that it depends on the kid and the circumstances, as has been clearly stated in other's wise answers. Can't add to the wisdom.
However, I want to add a couple of things to consider.
First, before allowing such a young teen to have transportation of any kind around town, I'd sit down and come up with a contract between teen and parent. Certain safety rules: helmet worn AT ALL TIMES, no headphones or ear buds, no cell phone use, consistent use of a very secure lock. And some kind of consequences laid out in clear language. If the bike and the kid are out and the helmet in still in the garage, loss of the bike for 2 weeks. If you see him riding up to the house taking the ear buds out, ditto. And if the bike isn't properly stored at home in the designated place, ditto. That kind of thing. Have him sign the contract.
Make sure that the bike is photographed, and the serial number is safely recorded (in case of theft). He should know his bike's identifying info. He should know it's place of purchase and the price, and any upgrades (a better seat, better tires, etc).
If you get an electric bike, know that those are very expensive (they can be as much as a small used car in some instances). Check with your homeowners' insurance about insuring it, and make sure that your teen is completely involved with the insurance process. He should know the name/number of the insurance company, and what the premium is, etc.
And make it clear: if the bike is misused, lent to a friend, left behind, not locked, and it's stolen or not returned, you won't just replace it. Treat this as the first step towards car ownership or privileges and treat the bike in much the same way. It's a good life lesson in responsibility. You'd be amazed at how many kids have no idea who their car insurance company is, or how to call them, or that it costs money, and they're licensed young drivers. Their parents haven't taught them these important facts.
Also, he needs to know bike rules for riding on roads (riding with the traffic, obeying traffic signals and signs, not riding on sidewalks, etc).