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Light, and blue lights in particular, are the element that more than anything else heavily influences our sleep.
Wearing No Blue Light Glasses two hours before going to sleep typically solves sleep problems by 95%.
However, there are other small variables that, especially in the case of chronic insomnia, can help further improve sleep.
In the manual "Fall asleep in a flash and sleep like a log" you will discover the 8 more points that can compromise (even if only minimally) your sleep and how to avoid them.