Loader.bin not launched on newly flashed Pi 3

I’ve been trying to add a new unit to my application for a while now.
I’ve flashed the SD card using Etcher, but when I power up my Raspberry Pi 3 B+ it doesn’t come online. In stead, the green LED flashes 4 times, which apparently means “loader.bin not launched”.

What can I try? SD card (8GB) and Raspberry Pi are both brand new.

I was able to get my unit online after I reviewed the WiFi settings on the image.
It seems my Google Chrome autocomplete was the issue.