The due date isn't just a formality
The due date is the deadline by which the client has to pay. The term you choose, 7, 14 or 30 days, isn't just a convention, it decides when you actually have money in your account, not just on paper.
How to choose the right term
A term that's too long (30+ days) creates a real gap between expenses and income. A term that's too short can feel aggressive to large clients with slower internal payment processes. A 14-day term is usually a reasonable balance for small businesses.
How to keep track
See at any moment which invoices are close to their due date and which have already passed it, so you can act before it becomes a cash flow problem, not after.
Bottom line
The due date is a tool, not just a date. Use it to plan your cash flow, not just to tick a box on the invoice.