Many non-native English speakers incorrectly employ the expression 'at the end' instead of 'in the end'.
'In the end' is a synonymn of finally:
"All 5 candidates were suitable for the position, but in the end we chose David, who had more experience of negotiating with Chinese companies."
"We couldn't find suitable premises in the business district and in the end we decided to stay where we were."
At the end literally refers to the end of an event or a period of time. It DOES NOT mean finally. At the end is the opposite of at the beginning or at the start of, as the following examples illustrate:
"At the end of the day, many English people go to the pub, before returning home."
"At the end of my presentation a member of the audience asked a rather awkward question which I had difficulty answering and in the end I had to admit that I couldn't give him a clear answer."
