Imam al Nawawi (rh) mentions that a person needs to safeguard his tongue except from good speech or something beneficial. If he doubts the benefit of his speech he stays quiet.
Imam al Nawawi (rh) quotes Shaafi’ee (rh): If someone wants to speak he should think before he speaks. If there is a benefit then speak and if he doubts then stay silent.
As one of the people of the past said he counted the number of flaws in man up to 8,000 flaws.
If a person guards their tongue, they are protected from these!