Why is the bootable USB flash drive not being written via dd?

Question

linux

I want to write memtest to a flash drive, downloaded the img image, then:

sudo dd if=/home/user/Загрузки/memtest86-usb.img of=/dev/sdb

As a result, it is recorded, I reboot, I start it from a USB flash drive, and the message on the screen is: "Reboot and select proper boot device or insert boot media, No bootable device"

Answer 1

We recorded a floppy disk image, and the flash drive is defined as a hard disk. Or vice versa. In general, if I understand correctly, this is the problem.

Answer 2

writing an image via dd to a flash drive does not mean making it bootable