Because the work is in one place, the hours in a notebook and the invoice in a template. Every month the three are joined by hand, usually on a Sunday, and the total is an estimate of what was actually done.
Then the chasing starts, in a mailbox, with no record of who was reminded when.
Time is logged against the task as you work, priced from your own rate card, and becomes the invoice without being re-keyed. What you sold and what you delivered are on one record.
Payment state sits there too, so an overdue invoice is a dated fact with a reminder attached rather than a thing you feel guilty about.
It will not make a client pay. It gives you a dated record of what was delivered, agreed and invoiced, which is what makes the chase short.
And it is more than a one-person operation strictly needs. If a spreadsheet and a template are working, keep them until the chasing starts costing real time.
A subcontractor becomes a second person on the same record rather than a parallel spreadsheet, and their cost shows against the project margin.
If a client relationship becomes a pipeline, Flow reads the same record — nothing to migrate, because the customer already exists.
Products, not integrations. Each one reads the same record, so a join is a permission rather than a sync job with a mapping screen behind it.
Possibly, until invoicing and chasing start taking a day a month.
Yes, priced from your rate card, without re-keying.
Yes, and track hours against it to see whether the price was right.
Half an hour on your own numbers is usually enough to say whether Loop is the right place to start.