This is a rule that I try to apply to myself every day.
I had a bad habit of answering immediately when somebody asks a question. The silence between the answer and the question made me feel uncomfortable when I was young.
This was because I admired people who could talk their way out of anything. I noticed that they answered so fast like they already beforehand what the question was. That immediate reaction or answer to a question was something I admired.
I tried to replicate this when I was younger and became pretty good at it as well.
Until I went professional with my work. Answering a question immediately can have a good impact. For example, to show that you know the material and am confident about it. But it can also go against you.
Imagine situations where somebody asks you a question:
Is this possible to do?
If you react within 0.1 seconds with no, it could come over as you don't even want to think about it or work on it. If you said yes in the other instance, you could shoot yourself in the foot, cause you may didn't even work on it.
This could be prevented if you took 3-5 seconds to think about it. That 3-5 seconds to think, can change the entire course of the conversation. During that time, you evaluate, formulate your answer, and also decide how to come over to the other person.
All this can be done within 3-5 seconds. If you need more time take more. It is better to have silence than communicate the wrong information and/or make the wrong decision.
Think before you speak!