Two girlfriends and some random trains

A man who lives in Andul has two girlfriends. One lives in Dasnagar which is to the east of Andul and the other lives in Bauria which is to the west of Andul. The man likes both of them equally but can only visit one each weekend. So every Saturday he goes to Andul station at some random time and catches the first train that comes. Trains in both directions arrive equally often. To be precise, every ten minutes one can get a train from Andul to either directions, i.e., towards Dasnagar and towards Bauria. However, after an year he finds himself visiting the woman in Dasnagar on an average nine times out of ten. How could the odds be so heavily in favour of the Dasnagar train?

Solution