I noticed a couple of discussions on here about Edison being stuck in a boot-cycle or continuously re-booting.
In some cases it gets to "ready to receive application" and then reboots.
So I did a bit of experimenting and discovered that some laptops (such as my Lenovo ThinkPad T450) cause an Edison to continuously re-boot, whereas others such as my Dell Latitude or my iMac Desktop do not.
I don't know exactly what is happening, but it seems that at some point during the boot-cycle the power available from the USB port during the boot cycle is insufficient, causing the Edison to reboot.
It is possible that the USB port starts out by supplying a lower power limit, which is not enough for Edison to transition from bootloader to full boot. Or maybe the USB Port actually removes power at some stage.
The solution for me was to use a mains USB Power supply to power the Edison rather than trying to draw power from a USB port.
If you have an Edison which won't boot, it would be worth powering it from a USB Charger rather than a USB port on a laptop/PC and see if it can then fully boot.