Indian film history is many decades old. It has many stories to share. Here we are talking about story as mentioned on Wikipedia.
As per Naushad, Rafi came to him with a letter of recommendation from Naushad’s father.
Before Rafi, Naushad’s favourite singer was Talat Mahmood.
Once Naushad found Talat smoking during a recording.
He was annoyed and hired Rafi to sing all the songs of the movie Baiju Bawra.
Such things can happen with anyone. But it’s important to be disciplined when you are on work.