bro i was also facing this issue for many years but no one is able to fix ... i replaced 8 self motors but after 1 month it came back.....
3 days back ... a mechanic drove my honda city he said
"grm ho k ni chaldi?ho jaegi set"
he connectd his new battry car was startd at half self ....then he changed battery terminal and cleaned ground cable... mashallah nw its working v gud