Discuss and learn French: French vocabulary, French grammar, French culture etc.
it means "what's the use of doing...?"
this is a common question in english so i'm sure it's common in french. more common would b to say "what's the POINT of [going, doing it that way, rushing, etc.]
it would b easier for me to say "a quoi bon [partir maintenant, etc.]." would that b ok?
"à quoi celà sert de faire.... ?" the right form is "à quoi celà sert-il de faire...?" it's a bit formal.
in a conversation it's rather "à quoi ça sert de faire ...." and this is a common question in french.
with "celà" it sounds odd without "sert-il" and with "ça" it doesn't sound odd.
"A quoi bon ...." is used too, it's just more formal but nobody will be surprised by this way. But the meaning is slightly different.
A quoi ça sert de manger : means you want to know why you have to eat or why you eat. But you ask just to have a answer. The context implyes (implys ? implies ?) that you mean it's useless. But the first meaning is just to have an answer.
A quoi bon manger : means the same thing but you ask with the idea that it's useless, that it doesn't make any difference. A quoi bon courir, je ne perds pas de poids. nobody will be surprised by this way. It's commonly used. maybe a bit formal but used.
there is another way, a bit formal.
"A quoi sert de ...." without "celà" ou "ça".