[Ruling on being led in prayer by one who is not the most entitled 3]

Answer (and Allah grants success): If his being put forward was after consultation and ijtihād by the righteous people, then the congregation has its virtue, and that does not diminish it—because the opinions of the righteous in a town may differ regarding who is most entitled to lead; in such a case, one should not leave that congregation.
But if he was put forward without excuse, without permission, and without the deliberation of the righteous and their appointment—then that congregation has no virtue, and there is no blame in leaving it.
There has come a threat from the Prophet—may Allah bless him and his family and grant them peace—against one who leads a people while they dislike him; and in another ḥadīth: “If it pleases you that your prayer be purified, then put forward your best.” And in another: “Your imāms are your envoys to Allah, so look with whom you send (yourselves).” And in another: “No word, no deed, and no intention (is accepted) except with conformity to the Sunnah.”
Source : Min Thimār al-ʿIlm wa al-Ḥikmah vol.1