Ask a freelancer about cash-flow problems and they'll tell you about late-paying clients. Real problem. But there's a quieter, more expensive one almost nobody tracks: the work you finished and never invoiced.
The extra revision you did on Friday. The "quick favor" that took two hours. The milestone you completed but forgot to bill because you were already deep in the next project. None of it is "late", it's just invisible. And invisible work is unpaid work.
Why it happens
Invoicing is a context switch. You're in maker mode, designing, writing, coding, and stopping to log billable work breaks the flow. So you tell yourself you'll "do invoices later." Later, you can't fully remember what you did. You round down. You skip the small stuff. Over a year, that rounding-down is real money.
The fix: a running "unbilled" list
