From my childhood till now I have listen that there are three words I LOVE YOU to express your love but in Fridays episode dev said that he is unable to speak 4 words to express his love to nandini.
But as we all know dev tis the most experienced lover in GHSPš as he has loved three times in th e serialso he may know more than us about love .or he had loved more than one girl in his life so to express his love he had to speak their name also so he must say that he has to say 4words to express his loveš
772