Errors Are Not Just Errors

We often say, 'mistake is a mistake' to mean and to emphasise that big or small, both positive and negative mistakes should be condemned. But in real life situations, all of us want 'to err on the positive side' and 'give benefit of doubt' while judging something or someone. In other words, errors are of two types. Shall we call them harmless, soft or positive error and harmful, harsh and negative error? Take the example of announcing results of an examination or a test. A student 'A' who has really passed, but the system has by mistake declared him as failed and another student 'B', who has really failed the test but declared as passed. The former is a negative, harsh and more harmful error than the other.