Honestly the major issue falls under Road design which is abysmal in our country. Let me give an example of an state of bus stand and how it connects to an road.
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This is the new constructed Chennai Mofussil/State government bus stand. Largest in our country. And the road which is running in the photo is the NH44 Chennai - Kanyakumari Highway. The entire stretch from Chennai to Chengelpet section is urbanized so much this Highway looks like an typical city road. Now about 100s of bus everyday will join the road in an 90 degree fashion into an High speed Highway.
In festival time of Diwali, Pongal good luck trying to cross the section as even huge busses will encroach the highway and moving out 25km from chennai will take 8 hours. (Happened in Diwali few times).
We have lot of examples of this joke design where High speed Highway met an small road at 90 degree. Also NHAI babus were too stingy they allow cost cutting of VUP in lot of sections. End result over the period of time lot of accidents happens and after many year they will start the work. Same NH44 have an famous accident point where People were asking for VUP for decades.