Say the thing once, clearly, and then stop. Most people weaken a good point by explaining it again, adding a qualifier, and checking that everyone agrees. Each extra sentence makes the first one sound less certain, and the silence you are trying to fill is usually not a problem.
What over-explaining actually signals
Your point lands. Nobody responds immediately. The pause feels long, so you fill it. You rephrase. You add an example. You add "but obviously it depends".
To you that felt like being helpful. To the room it reads as someone who is not sure, because a person who was sure would have stopped.
The pause was not disagreement. People were thinking, or looking at their notes, or waiting to see who speaks next. Three seconds feels much longer when you are the one who just spoke.
Why quiet people fall into this specific trap
This looks like a confidence problem and usually is not.
If you rehearsed what to say, you probably rehearsed more than one version. When the first lands in silence, the other versions are right there, and saying one feels like the natural next step.
There is also a real physical thing happening. Wanberg, Park and Gracen studied what happens when work asks people to do something that cuts against how they naturally operate. Being put on the spot came up as its own kind of pressure, and people felt it before, during and after. Filling a silence is what that pressure does when it has nowhere to go.
So the fix is not being braver. It is knowing in advance that the pause is coming, and that it means nothing.
What to do with the silence
Say your point in one or two sentences and then close your mouth. Count to five in your head if that helps.
Someone will respond, or the discussion will move on. Both are fine. If nobody responds and you think it mattered, you can say one short line later: "I want to come back to the timeline point, I do not think we settled it." That is far stronger than repeating yourself in the moment.
If you are worried it was not clear, ask rather than explain. "Does that make sense as a concern?" puts the next move on them and takes one sentence.
Say less than feels comfortable. What you did not say cannot be used against you. What you said cannot be taken back.
How to tell which kind of room you are in
Some rooms treat brevity as authority. Others read it as not having done the work, especially if you are new or if people do not know your track record yet. That difference is real and it changes what you should do.
You can find out by watching, without testing it on yourself first.
Watch what happens when someone else says something short. If a senior person makes a one line point and the room moves on, brevity carries weight there. If someone asks them to expand every time, this is a room that wants the reasoning out loud, and saying less will read as having less.
Watch who gets interrupted. In rooms where short statements are respected, people finish. In rooms where they are not, a short point is treated as an opening someone else can take.
Then adjust one notch rather than switching. If the room wants reasoning, give your point and one line of why, and still stop. That is shorter than what most people do and it fits a room that would find bare statements too thin.
If you are new, say the point and the evidence for a while. Brevity works best once people already trust your judgement, and that is earned rather than assumed.
The part that stays yours is the specific read. You know things about your manager and your team that no article does. What this gives you is what to look at.
Stopping short is only one way to do this. There are others, and which one fits depends on how much standing you already have in the room, which is worth thinking about properly rather than copying whoever seems confident.