This is the 5590th most frequent Arabic word.
فلماذا
"So why"
The word 'فلماذا' is used here as a questioning lead to introduce a suggestion for recommencing an effort.
فلماذا لا نحاول مرة أخرى؟
So why don't we try again?
'فلماذا' introduces a logical continuation of a thought leading to a proposed action based on a stated condition.
أنا متعب للغاية، فلماذا لا تستريح قليلاً؟
I am very tired, so why don't you rest a bit?
Here, 'فلماذا' serves to question someone's lack of action in connecting to previously presented information.