Why not see a patient in Taiyin 369?

This may be related to figures and the saying that "seven don't go out and eight don't go home". People often say, "369, go out", "seven don't go out, eight don't go home", which means good luck. Three three see nine, six six is great, and nine nine is one. This is an auspicious word among the people. If you don't go out seven times, you won't go home eight times. I'm afraid it has something to do with the idiom "seven ups and eight downs". People in a bad mood, things are in a mess, and people in a bad mood don't go out, which means something will happen.