The instruction manual says "avoid looking directly at the light source", but is the light really harmful?

The instructions that say "avoid looking directly at the light source" are mainly for the perspective of safety reminders. UV LED nail art machines use ultraviolet (UV) light, and although our products use a low-power, safe-band UV-LED light source, which is safe for the skin and the environment, looking directly at the bright light for a long time may cause irritation or discomfort to the eyes.
Just like sunlight, while it is safe for daily contact, it is not recommended to look directly for long periods of time. Therefore, as long as you use it according to the instructions and do not deliberately stare at the light source, it is safe and will not cause harm to the eyes.