
So what are the three things, and are there any scientific reasons?
First, no way to go out
No way to go out does not mean that there is no way at the door. There is a road parallel to the house at the door, which is convenient for travel. The road here refers to the T-junction, and the gate is at the junction of the T-junction, which is also called a dead-end road.
This location is an intersection, and is where vehicles and people gather. Because there is a right-angle turn here, vehicles are prone to rush into the courtyard.
When the past, when the war was in chaos, the house was in this position and was easily disturbed by evil people.

Second, don’t see the tree when you go out
It is a good thing to have a tree at home. It can shelter from wind and rain, but it depends on the location and cannot be directly facing the door.
tree faces the door, blocking all the light. The door is not bright, and it blocks people's way out.
Think about it, if a person’s way out is blocked, can he still have a good future?
On the other hand, there is a tree in front of the door, so it is not convenient to carry some things.

Third, no tigers can be seen when going out
Everyone knows that tigers are very powerful animals. When building houses in the past, there would be tiger sculptures on the ridge or on both sides of the eaves, which would have the effect of suppressing houses and warding off evil spirits.
Later, the tiger head refers to everything sharp and sharp. If the tiger carving on the eaves of other people's house is heading towards their own door, it is not very good.

Of course, these are the subjective imaginations of the ancients and have no scientific reason.
And now they live in buildings, it is difficult to encounter these phenomena. Are you right?