Why does not see a smartphone through ADB?

Question

Android

Asus 5 4.4.2
Debugging enabled via USB.
I did the following: turned off the smartphone
--> then held down the volume + power button
--> went into the bootloader and selected the recovery item
I wanted to connect via ADB, but does not see the device.
Here's what it actually outputs:

Answer 1

The installed recovery does not support ADB. Install for example TWRP, it can ADB sideload.