What does it mean to guard against gentlemen and not villains?

This gentleman is not a real gentleman, and a real gentleman naturally needs no precautions. This gentleman refers to a kind of person who has basic moral cultivation, but may not strictly abide by the current moral norms. Call it a civilian for the time being.

Suppose there is a house in which some valuables are stored and locked with a simple password lock. The password was recorded on a memo on the desk not far from the door, and the content was deliberately blocked. This is to prevent gentlemen from guarding against villains.

Passing gentleman: Whether he knows the password or not, he won't try to open the door without the owner's instructions.

Civilian passing by: Seeing the password lock, but the password is unknown, then based on his own cultivation, he will not rummage for the password and try to open the door. But if the password is clearly placed by the door, or other places within reach, then he may not open the door now after getting the password, but the password is written in his mind. Under the circumstances at that time, something would inevitably happen (for example, I accidentally learned that there was something I needed urgently), and finally I secretly opened the door driven by interests. The so-called gentleman to guard against it, to guard against it is like this.

Little people pass: little people see it, so it's not a question of locking or not, it's a question of unlocking difficulty.

Some people say that this is the golden mean, which is suspected of being negative. In my opinion, it's like the lazy mode/hungry mode of a computer, and it's just the optimal solution in a specific situation.