The Messenger of Allah ﷺ said: “If two men come to you for judgement, do not rule in favour of the first one until you listen to what the other one says, then you will know how to judge.” He said: Since then I became a good judge. (Using translation from Aḥmad 1211)
قَالَ رَسُولُ اللهِ ﷺ إِذَا تَقَاضَى إِلَيْكَ رَجُلَانِ فَلَا تَقْضِ لِلْأَوَّلِ حَتَّى تَسْمَعَ كَلَامَ الْآخَرِ فَسَوْفَ تَرَى كَيْفَ تَقْضِي قَالَ فَمَا زِلْتُ بَعْدُ قَاضِيًا