When a company doesn't pay on time without forewarning, it tends to be a bad sign in regard to their financial picture. It is not uncommon for companies to experience temporary problems with cash flow, but when the picture is positive in the short term, there's less incentive to avoid the unpleasant conversation. When the outlook is grim, decent people (and most people are) want to avoid lying and so the conversation gets put off.

To put it another way, employees are usually the last people to not get paid. Vendors, landlords, utility companies, etc. are much easier to delay, e.g. landlords don't want to evict tenants because of the associated expense. Employees are likely to just stop showing up.

On the bright side, if you always wanted to be a bank offering zero interest loans to companies that don't pay their employees, this is your chance. Because apparently the company cannot borrow money to cover operating expenses.

Good luck.