One of the most stupid films in terms of plot holes is the 1997 Bollywood film Hero no 1 (a fairly enjoyable but utterly illogical movie), a mix of DDLJ and Bawarchi.
So, the heroine tops the college and gets a trip to Europe (which college and University and this in India). The grandfather doesn't allow her. After a lot of persuasion he does allow her to go, but with her Bua (who paid for her expenses. The film showed that out of the three brothers, one is a college lecturer, another a failed Insurance salesman and third a struggling musician, so who exactly paid for her trip).
Now, the girl checks in a private luxury hotel (did University paid for it?) where our hero, the son of a rich man is also staying. The heroine does nothing academic in her whole trip, and we don't know what the trip was about till the end. She ends up romancing the rich hero and the bua facilitates her.
Back in India, there is some misunderstanding among the father of the boy and the grandfather of girl and the proposed alliance is called off. Now our hero plans to win the hearts of the girl's family by pretending to be a cook.
When our heroine decides to pursue further studies she is shut down and sent to her room to cry. Except for the fact that she was shown carrying 3 books with her going to college. When did she get admission for higher studies? Which books are she carrying because she apparently has not taken admission anywhere?
In Bawarchi, there was a reason why the cook knew cooking, mathematics, philosophy, music and dance etc. In Hero no 1 there is no reason and makers gave no reason whatsoever. Nobody even cared to know how their prospective groom looked like so nobody could identify the hero disguised as cook.
He sings with the girl “Main Tujhko bhaga laya hun tere Ghar se tere baap ke dar se” (I have eloped with you away from your home, for the fear of your father) when clearly the girl’s parents died years ago.
Even though the grandfather hated the boy’s father badly he apparently couldn't recognise him when he came in a disguise with a beard (tough competition to Rab ne Bana Di Jodi).
Even though the salesman brother of the family got insurance worth of many lakhs because of boy’s father’s company he didn't care to know why all his clients came from the same company.
Even though the second brother got saved from getting transferred to remote area due to boy's father he never cared to know how and why the education minister recommended him.