Majorly you would perform due diligence which is a kind of investigation, when you are entering into a transaction with some other party. It is typically more important for the buyer than the seller. If you are a buyer, you would conduct your due diligence before the transaction is finalized to verify if the acquisition is worth it. Hence before signing off the deal, performing a due diligence is the best way for you to assess the value of a business and the risks associated with buying it.