Sad news. It seems Model Power helped get and keep many in various scales of the model railroad hobby. This is another bad sign for the model railroad hobby. These continued losses of a local hobby shop retailer here and supplier/mfr there, combined with the hobby's aging demographic is a troubling and demoralizing trend of a once powerful hobby and business. There is no positive takeaway from the Model Power news or this continuing trend. Consider for a moment how much the model train hobby (O gauge specifically) has changed in the last 5/10/20/30 years.
The rule of thumb for us hobbyists might be to make the most of the hobby and enjoy what it has to offer us now.
Speaking in general terms, because we do not have the all the details, but it has been more prevalent for banks or financial firms who would lend against a company's inventory to no longer offer this collateral based finance option because of the typically higher risk to the bank. Now this change in lending practice by the bank may be not as a result of this specific borrower's ability to pay, but due rather to the performance of the bank's overall existing loan portfolio. In other words, a lender who was has a number of bad apple borrowers will also negatively impact those good apple (paying) customers. Furthermore, as AMCDave points out, the cost to manufacture in China has grown significantly in the past few years. Even though there still is "profit" to be made, sometimes that amount of profit is not enough for some lenders.
If some of the bank's other customer loans are not performing well, then the bank will likely (either self imposed or by bank regulators) reduce its exposure and overall risk by changing their lending practices to be more conservative (i.e. tight). Banks will "cut off" a longtime customer by and not limited to: calling for full payment of the customer's loans, upon end of the scheduled loan not renewing the borrower's line of credit, greatly increasing the pricing to the borrower or making the borrower's loan covenants (performance ratios) unattainable - in effect forcing the borrower to find financing elsewhere to pay off the bank or liquidate the business.