Among the mistakes that occur when going to Mina: 

Some people do not recite the Talbiyah out loud even though it is prescribed to recite it out loud. Crowds of pilgrims pass by and you can hardly hear anyone reciting the Talbiyah. This is contrary to the Sunnah and it is contrary to what the Messenger of Allah (blessings and peace of Allah be upon him) enjoined his Companions to do. The Sunnah is for a person to recite the Talbiyah out loud and to raise his voice if it is not difficult for him to do so. He should remember that nothing hears him, rock or soil, but it will bear witness for him on the Day of Resurrection before Allah, may He be glorified and exalted. 

Some pilgrims go directly to ‘Arafah and do not stay overnight in Mina. Although this is permissible, because staying overnight in Mina before the day of ‘Arafat is not obligatory, it is better for a person to follow the Sunnah, as it is narrated that the Messenger of Allah (blessings and peace of Allah be upon him) stopped in Mina from the forenoon on the eighth (of Dhu’l-Hijjah) until the sun rose on the ninth. The Messenger of Allah (blessings and peace of Allah be upon him) did that and he said: “Learn from me your rituals (of Hajj). Narrated by Muslim (1218). 

But if he comes to ‘Arafah and did not stay overnight in Mina on the night before the ninth, there is nothing wrong with that, because of the hadeeth of ‘Urwah ibn al-Mudarras, who came to the Prophet (blessings and peace of Allah be upon him) at the time of Fajr prayer on the day of Eid in Muzdalifah and said: O Messenger of Allah, I have exhausted my mount and tired myself. By Allaah, I have not left a single mountain but I have stood on it. Is my Hajj valid? The Prophet (blessings and peace of Allah upon him) said: “Whoever prays this prayer with us and stands with us until we move on, and stood before that in ‘Arafah by night or by day has completed his Hajj and fulfilled his duties.” Narrated by Abu Dawood (1950).

 The Messenger of Allah (blessings and peace of Allah be upon him) did not mention staying overnight in Mina on the night before the ninth. This indicates that it is not obligatory. 

Another mistake that people make with regard to staying in Mina on the eighth is that some people shorten their prayers and join them in Mina, so they join Zuhr and ‘Asr, and Maghrib and ‘Isha’. This is contrary to the Sunnah. What is prescribed for the people in Mina is to shorten their prayers without joining them. This is the Sunnah that is narrated from the Messenger of Allah (blessings and peace of Allah be upon him). Although joining prayers is permissible, because one is travelling and it is permissible for the traveller to join prayers whether he has halted or is on the move, it is preferable for the traveller who has halted not to join prayers unless that is for a reason, and there is no reason that would dictate joining prayers in Mina. Hence the Messenger of Allah (blessings and peace of Allah be upon him) did not join his prayers in Mina but he did shorten the four-rak’ah prayers to two rak’ahs, so he prayed Zuhr with two rak’ahs at its proper time, ‘Asr with two rak’ahs at its proper time, Maghrib with three rak’ahs at its proper time, ‘Isha’ with two rak’ahs at its proper time and Fajr at its proper time. End quote.