Woolcombers of India Ltd. v. Woolcombers Workers Union and Anr. AIR 1973 SC 2758,

The giving of reasons in support of their conclusions by judicial and quasi-judicial authorities when exercising initial jurisdiction is essential for various reasons. First, it is calculated to prevent unconscious unfairness or arbitrariness in reaching the conclusions. The very search for reasons will put the authority on the alert and minimise the chances of unconscious infiltration of personal bias or unfairness in the conclusion. The authority will adduce reasons which will be regarded as fair and legitimate by a reasonable man and will discard irrelevant or extraneous considerations....