Lord Reid said,
…I have taken as my subject today the judge as law maker. The jurist may ask what I mean by law…. the practical answer is that the law is what the judge says it is. Before a point of law has been decided in court counsel must be guarded in advising his client… A decision of the House of Lords is final not because it is right but because no one can say it is wrong-except writers in legal journals.
There was a time when it was thought almost indecent to suggest that judges make law-they only declare it. Those with a taste for fairy tales seem to have thought that in some Aladdin’s cave there is hidden the Common Law in all its splendour and that on a judge’s appointment there descends on him knowledge of the magic words Open Sesame. Bad decisions are given when the judge has muddled the pass word and the wrong door opens.
But we do not believe in fairy tales any more. So we must accept the fact that for better or for worse judges do make law, and tackle the question how do they approach their task and how should they approach it. It takes all kinds to make a world and I do not think that the day will or should ever come when every judge is a legal pundit. Nine-tenths of the time of a judge at first instance is taken up with getting at the facts-keeping control of the proceedings, watching the witnesses and evaluating the evidence. More often than not once the facts are determined the law is clear. If it is not and the judge goes wrong the Court of Appeal can set him right. But if he gets the facts wrong his mistake is generally irretrievable…’

You can find this article on Heinonline. The citation for the original is Journal of the Society of Public Teachers of Law (New Series), Vol. 12, Issue 1 (January 1972), pp. 22-29.
[Edited and formatted for ease of reading.]