Root Unlock your bootloader @ Developer Options

[horsecharles]

The usual...
Go tap the Build Number seve(ral) times, and tick Unlock Bootloader.

 

[xyourxhighnessx]

That won't unlock the bootloader

 

[Masterchief87]

That won't unlock the bootloader

Clicking the OEM unlock box in developer options doesn't unlock the bootloader.

If you do unlock the bootloader you'd lose everything and start over. Once the bootloader is unlocked you tick that box in dev options

Not correct. I had a Stylo, and on the Stylo the bootloader is unlocked the moment you tick that switch(without erasing your data), and as soon as you turn it off the bootloader is locked again. I know because I accidentally turned it off when I had twrp installed and it soft bricked the phone requiring me to flash the stock firmware.

With nexus devices however, that option only allows the bootloader to be unlocked but does not actually unlock it. With a nexus device you have to enable OEM unlocking in development options then reboot into the bootloader and unlock it with fastboot, which does factory reset the device in the process.

To sum it all up in one sentence, what the OEM unlock option in developer options does or doesn't do is all up to the developers who make the device's firmware.

 

[xyourxhighnessx]

For the Stylo I clearly remember typing "fastboot OEM unlock" and losing all data.

 

[xyourxhighnessx]

But yes you may be right that it's up to developers on how they implement it

 

[Masterchief87]

For the Stylo I clearly remember typing "fastboot OEM unlock" and losing all data.

If that is the case, it was after the marshmallow update. On lollipop, fastboot didn't work on the Stylo. This confirms what I've been saying that it is up to the firmware developers what the OEM unlock option does or doesn't do.