Because you need to generate financial statements. Without an AP/AR opening balance, your statement will not be consistent with your previous records unless you are truly a newly-formed company and setting up netsuite at company inception.

This is pretty concise. Thanks!

@Mars For importing AP/AR opening balances have you seen documentation of the best practices for that? I want something third party to be able to show to my accounting department.

I don't know of any 3rd-party. You can look in to the Netsuite books. But I've found that the tricky part is the setting up of Chart of Accounts. If you set an account with a different type, some transactions will only allow GL changes to a specific type of account. Common interchangeable account types that you should ask your implementation partners: 1. Accounts receivable type vs. Other current asset type 2. Accounts payable type vs. Other current liabilities type There are more but these two should be the usual suspects.