What is wrong in the sentence you need it by

The sentence "You need it by" is incomplete. It lacks context and a specific time or deadline. To make it a complete and meaningful sentence, you need to add:

* What "it" refers to: What item or task is being referred to?

* When the deadline is: What is the specific time or date by which the item is needed?

Here are some examples of complete sentences:

* "You need the report by Friday."

* "You need to finish the project by 5 pm."

* "You need the tickets by tomorrow morning."

Let me know if you can provide more context, and I can help you create a complete sentence.