I've never actually found an iPhone using Find my iPhone. It never updates.
That's because there's no actual GPS on it. Something that can locate it even when it's locked.
My personal information must be protected. I used everything including Touch ID. I'll probably never remove the phone from my account, because that would allow the phone to be used.
It's going to remain locked and hopefully someone can figure out how to connect it to a Wi-Fi network so that it can erase itself.
I doubt the person who has my phone found a charger for it. I doubt they even know how to use an iPhone.
Lots of people I've seen now just steal the iPhone but then can't use it. They take it everywhere and say, "I can't use this phone, I don't know that Apple user's ID..."
They go to the carrier store, they go to their friends, they go to Apple... smh
Ok. I see the frustration.
I would bet money this is due to the phone being turned off, with the SIM card removed, probably already fenced, waiting to see if they can wipe & resell.
In that case, the phone getting turned back on will present a passcode lock (assuming you use one) and activation lock will make it difficult for them to sell. 99.9% likelihood that your data isn't interesting to them.
Basically there are two types of theives.
Those who know what their doing, and the clueless idiots.
While we all wish for the clueless idiot type, (turns on phone, tries to call his girlfriend while joyriding in a stolen car smoking a blunt) smarter theives are the ones who do this for a living. Spend time in jail for stealing stuff and you'll either get smarter or you'll just go back and spend more time in jail. Darwinism isn't kind. At all.
Most people with at least minimal brain function know that a cell phone is easy to track. Cellular triangulation has been around for a long time and doesn't require anything special to work. So the phone is immediately turned off, the sim is removed. Unless your phone was swiped by a complete idiot, that's what happened.
While GPS is a passive technology that only needs to receive to work, the device still requires 1) some sort of data connection to broadcast its location, (Cellular or wifi) and 2) electrical power to do the broadcasting with. GPS chips in devices do not broadcast, only receive. And as far as I know, the law requires removable batteries or power buttons that really and truly turn devices off, so hidden powered on functionality is kinda out of the question.
So unless they turn it back on and it had a way to phone home, find my iPhone isnt going to give you a location.
Finally I think there is some confusion about what find my iPhone is for. It isn't meant as a theft tracking device. It is designed to locate lost/misplaced iDevices. Wake up Sunday morning without your iPhone and use FMi to figure out in which bar/restaurant/designated drivers car you left it in.
While it can be used occasionally to find stolen devices (see clueless idiots above) FMi's abilities there are limited.
Activation Lock is what is designed to prevent theft. This prevention however is on a macro level, not a find my personal stolen device dammit level.