Because personal development is limited.
But the breadth of friends is infinite.
Communicating with different friends (as long as they are not bad friends) will always experience different lives in different ways.
Communicating with them can bring different experiences and ways of thinking
You will find that maybe what you think is not the only answer or life can be like this.
You may disagree with them.
But don't be too specific.
It is friendship that lives in peace and flows smoothly.
There are people standing around at all times.
When you are happy, someone makes you feel that you can share it with them.
Don't feel lonely when you are sad.
What are the disadvantages?
Don't meet bad friends.
Maybe it makes you lose the power to trust others.
Or is it bad for you?
So, of course, you have to have your own opinions.
Seek common ground while reserving differences.