Jack Lemmon made a slight change to the script
Only very slight but as classic film fans would know, Billy Wilder/I.A.L. Diamond scripts couldn't be changed as they were always perfection. Jack Lemmon said you couldn't add or take away a word. It would be like trying to ad-lib Shakespeare.
But the line to which Jack Lemmon says in Sig Poliakoff's office "Now you're talking" was originally in the script to be said once but Jack wanted to say it twice, with the emphasis on the word 'now'. Billy agreed and allowed him to say it twice. And it works so well! I love the way he says it.
Marilyn Monroe: I don't want to be rich. I just want to be wonderful.