Have you ever tried to get an invoice paid by an a*hole customer?
It's not exactly that. The post names it "Accounts Receivables as a Service". The idea is to make sure the invoice does not become a bad debt.
The willingness to pay small vendors and contractors varies across countries, industries, and cultures. Often, it involves a ridiculous amount of haggling and bickering.
For a small business, it is a lot of pain and loss of productivity (let alone actual revenue in some cases).
It's not technically ambitious but definitely a real problem to be solved.