Always telling the truth is the most important consideration in relationships,: do you agree or disagree?
No one wants to be friends with people who always tell lies. Telling the truth is obviously one of the most important characteristics of a person. However, is 'always telling truth' the most important consideration in any relationship between people? The answer is no. Telling the truth is important, but a white lie will be more welcome when the truth means harm is hurtful.
Admittedly, truth is one of the foundations of relationships. When people always tell lies, the truth will come out one day, and the liar will lose credit credibility on with others. The person who has been cheated will be disappointed and may never trust those who lie again. For example, there is a famous old story about a shepherd boy. The shepherd boy shouts: "Help! Wolves come are coming!" when there is actually no wolf coming, just for fun. When the wolves really come, he shouts for help again, but no people come to help him. Therefore, to keep credit good maintain their credibility, people should tell the truths.
However, the truths are is not the best choice in every case. Sometimes the truths may mean harm be hurtful and a lie may comfort others, and that's what most people do every day. When your teammate makes a fetal fatal (?) mistake, the most wit (?) action is not yielding yelling at him/her, but to say that it is ok and find out a solution together. When a dying mother asks about her son who has just died in the battle, any kind-hearted person will tell her that her son will come back a few days later, which will never realize. A white lie may bring peace to others,; the truth should be placed behind.
To sum up, in most cases, we should tell the truth. But in special cases where the truth means harm is hurtful, we could choose to tell a white lie.
I'm sorry, I don't understand what you meant by "the most wit action". I'm also not sure what you meant by "fetal mistake". "Fetal" means having to do with an unborn child. "Fatal" means deadly. I'm not sure that either applies in that sentence.
"Wolves come" is grammatically correct, but it sounds odd to a native English speaker, as the form "wolves are coming" is normally used to indicate the present tense. I put a comma before "just for fun", but it would sound less awkward to say: "just for fun, when there is actually no wolf coming."
In modern English, "credit" usually refers to the ability to go into debt to buy something. I chose "credibility" because I thought it was what you were trying to say, but I would just use "trust": "will lose the trust of others" or "will lose others' trust"; "Therefore, to maintain the trust of others, ...".
It would be a good idea to learn where to use the colon and semicolon, although to be honest, many native English speakers don't bother with them and use commas instead. I put "do you" before "agree or disagree" because otherwise it would be grammatically incorrect, although again many native English speakers would leave it out. Finally, many English grammarians will tell you that "but" is only used as a conjunction, after a comma, and never at the beginning of a sentence. Many native English speakers don't follow that rule, and I'm one of them, so I didn't bother to correct you. However, if you want to follow that rule, you should probably write it: "...we should tell the truth, but in special cases...."
Overall it is reasonably fluent and easy to comprehend, with the exception of that one "teammate" sentence.