Correcting Imam in Recitation

The prominent Saudi Islamic lecturer and author, Sheikh Muhammad Saleh Al-Munajjid, states the following: “If the Imam makes a mistake in his recitation- apart from Al-Fatihah– that does not alter the meaning, then you do not have to correct his mistake. This is something that no Imam is entirely free from. But it is better to point it out to him after the prayer, because this will help him to remember it.
However, if the Imam refuses to correct his mistake even though he knows it is a mistake, then one of the following two cases applies:
If the mistake alters the meaning, and he knows that it is a mistake but he does not correct his mistake after it has been pointed out to him, then you must repeat the prayer.
But how can you be sure that he realises that it’s a mistake and persists in it?
But if it is a mistake that does not alter the meaning, then you do not have to repeat the prayer, but you must advise the Imam in a kind and gentle manner, and explain that it is not something shameful if the Imam forgets something, for the best of Allah’s creation, Muhammad, peace and blessings of Allah be upon him, also forgot, and the Companions, may Allah be pleased with them all, who were behind him reminded him, as is mentioned in the Hadith, in which the Prophet, peace and blessings be upon him, is reported to have said: ” I am a human being like you and liable to forget like you. So if I forget remind me and if anyone of you is doubtful about his prayer, he should follow what he thinks to be correct and complete his prayer accordingly and finish it and do two prostrations (of Sahu)” (Reported by Al-Bukhari)