The main cause is drivers are not disciplined to follow traffic rules. They knew that driving should be done with extra care because life is put on the line but they just don't care even if they may involve other people.
I think the most commong reason of road accidents is recklessness due to different reasons. There are drunk drivers , sleepy and so on. The government must be strict and they should do something about it because road accidents are really increasing these days which kills innocent lives.
The government is very strict about road accidents. It's just useless if we ourselves do not have discipline.