해가 지지 않는 사이트
The Website On Which the Sun Never Sets refers to a website that is always active and in use by at least one user, with a global reach that allows it to be accessed from any location at any time of day or night. The concept of "The Website On Which the Sun Never Sets" is a modern metaphorical expression that refers to the global nature and constant activity of the internet. Just as the British Empire once had territories and colonies across multiple continents and time zones, the internet is a worldwide network that is always active and accessible anywhere.
To determine if a website fits the concept of "The Website On Which the Sun Never Sets," we can use the formula of average visitors per day multiplied by the average stay time.
If this number exceeds 1, someone is always on the website at any given time. This is similar to how the British Empire was said to have had territories in every time zone and, therefore, always had some part of it experiencing daylight.
The week-long version
Given my website has ~15s average screen-on-time, there should be 40K WAU to maintain such status. We can also add a probabilistic model, where the probability of no one on the site at any given time is less than < %. I guess the number should go approximately 100K WAU.