Because it chiefly talks about the poor international relationship between Pakistan & India. It makes fun of it; in every sequence, the lead couple debate as to why India & Pakistan is better in their own way. The comedy genre was lost somewhere in the middle.
Ali Zafar should just stop appearing in films; he is a good musician, why not stay as is? Yami Gautami's second stint in Bollywood is below average. But this is not where the film goes wrong. The lead actresses's family is a weird lot, having a prejudice for everything not Punjabi.
When thespians like Kirron & Anupam Kher act so badly, portraying characters that are not only half-baked but also illogical, you should get a fair idea where the film is moving. Then you have another hot- doll, which seems to be one the makers' daughter: flashing her figure all over the frame, flirting with her on-screen sister's fiancé simultaneously taking care of her over-smart child.
The father of the family is missing. Instead of being serious and and trying to find him, you have the wife making fun of her spouse's habits, the daughter drunk-dancing on top of a table, the son getting in a fight with Pakistanis and then befriending them, etc..
No script, poor direction, spontaneous dialogs, useless songs, no chemistry, poor editing and a very bad screenplay. The whole premise is so far from logic, I would've barfed if I would have stayed a minute longer in the theater. Who makes such movies? And I hear the producers of A Wednesday & Special Chabbis came together for this one. Well, terrible. Few humorous scenes made me chuckle 2-3 times, but that's it.
BOTTOM LINE: Never have I seen such an idiotic movie with no single factor to consider that after it got over, I looked at my partner and our expressions matched perfectly: that of disgust.