I was always in the business of knowing and understanding costs, so it surprised me how many apparently successful businesses failed ....
... and the most common reason is "cash flow". My Fay has helped several small local businesses succeed, or pull themselves out of a hole by helping them improve their cash flow.
You can be making a 50% profit on every part you make or every man-hour you sell, but if you don't COLLECT YOUR MONEY FROM YOUR CUSTOMERS at the same rate that you are PAYING OUT MONEY TO YOUR VENDORS, you will go right out of business and never understand why.
Very many people do not understand this, and when their business fails, they'll blame The Economy or The Current Administration or something ... and it's THEM!