Travel is the expense category that arrives in pieces. One trip becomes a flight on a card, a hotel invoice that shows up two weeks later, a taxi receipt in someone's coat pocket and a rebooking fee nobody remembers approving. In the ledger it all pools on a generic travel account, and matching the card statement to actual trips is the kind of work that gets postponed until it is genuinely hard.
Nance reassembles each trip in the administration. Spend booked through Navan is booked onto the right cost centers with its documentation attached, trip-level totals are matched against card statements and invoices, and refunds find their way back to the original booking. Travelers get asked for what is missing while they still remember the trip. Navan keeps running the travel; the books finally keep up with it.