the least said, the better

It is best to say as little about a difficult or unfortunate topic or situation as possible (to avoid making it worse or dwelling on it for too long). Can also be structured as "the least said about (something), the better." And when it comes to the company's previous failed product, well, the least said, the better. Look, I don't like their plan either, but moping about it won't solve anything. The least said about it, the better.

the less/least said, the ˈbetter

(saying) it is better in a difficult situation to say nothing or very little, because otherwise you might make it worse: He’s very angry and she’s very upset, so don’t say anything about cars or accidents. Remember, the less said, the better.