Learning to keep your mouth shut.
Yes some people have to learn this.
Many people give untimely comments and opinions.
People have gathered for the death rites of a person.
One among then goes to the wife of the deceased and asks - He must be having a good insurance coverage, right?
He amy be truly concerned about the welfare of the surviving family.
But the timing?
Many people are offending, unnecessarily.
In a group discussion someone says - "It's no surprise that we're behind schedule with this project, considering how utterly incompetent some people on this team are. Maybe if certain individuals actually did their jobs, we wouldn't be in this mess."
Everyone knows whom that targets.
This is an insult, not constructive criticism.
Many people are not ready to listen, they love their own voice and keep on talking.
They keep going from topic to topic branching out like how you click on link after link when you are browsing on the internet and eventually get lost.
The listeners also don't realize what you are trying to say.
These three are very bad qualities.
And you have to consciously train yourself to avoid these.

That's why our wise elders advice -
काले हितं मितं ब्रूयादविसंवादि पेशलम्।
पूर्वाभिभाषी सुमुखः सुशीलः करुणामृदुः॥

A group is camping deep inside a forest.
Suddenly they realize that they have run out of water.
One among them says - Let's gather water from the river, boil it and use it.
Timely and crisp.
He is not blaming anyone for planning the trip properly.
He is not giving 10 different options and confusing.

Some people would just object to whatever you say to prove that they are better than you.
It becomes a habit.
At some point it becomes so bad that if you agree with what they are saying, even that they won't like.
Mr. Mehta said - Isn't this place nice and well-maintained.
And you say - Yes, that's right.
He says - No, no, it is not always like this. It's because an NGO is taking care of it now.
You say - Oh, that's some good social work.
Mehta says - No, no, they are in it for money. They charge the municipality an exorbitant amount.
You say - Oh, is that so?
Mehta would say - No, no……
And something else.
You must have come across such people.

Not only should you avoid these three bad qualities.
You should also be courteous, kind, non-egoistic and soft with your words.
With these kind of words, you can achieve almost everything.
Mahabharata also says the same thing -
न हीदृशं सवननं त्रिषु लोकेषु विद्यते।
दया मैत्री च भूतेषु दानं च मधुरा च वाक् ॥