Why is the Rush Hour at 11 A.M. in Chennai??

This is something I am not able to understand. While the rush hour is generally between 8 A.M. to 10 A.M. in the mornings at most places, in Chennai, the RUSH HOUR seems to be at 10 A.M. to 11 A.M. and sometimes it extends up to 12 P.M. in the NOON also.

If we assume that most offices would open between 9 – 10 O’Clock in the morning, the rush hour ought to be 8 – 10 O’Clock, right? The maximum traffic ought to be at that time right?

But I’ve often noticed maximum traffic between 10 and 11 A.M. in the city. Are people supposed to reach their offices after 11 or what? If there are such offices, let me know – I’ll want to start working there NOW