'Robot' is an English word. Tamilnadu govt gives tax concessions only to films with pure Tamil titles. As far as the producer, director Shankar and Rajini are concerned, it does not matter whether they get tax concession or not. They don't mind retaining the title of 'Robot' but what about theatre owners?
The general public does not enjoy any concession, but it's the theatre owners who reap the benefits. Without any investment or hard work, the money is saved., so they would hardly let this go just like that without a protest. That's why the title matter had to be re-considered.
Shankar has given the translation in Tamil, so 'Robot' title is now 'Endhiram.' Just like 'Sivaji' had a sub-title of 'the Boss,' the new film title would be 'Endhiram - the Robot.'
News from Shankar's office has it that as the film progresses, even the title of 'Endhiram' could be subject to change.