There are some problems attributed with NPV. This may be due to many factors regarding the current value of a product or service.
Generally speaking a product or service may have a negative value whereby it can be sold at discounted rates. However the main problem is that in having a negative value and being sold for a set price that the buyer ultimately gets something that costs more than its real value. Another problem is that to avoid losses, a premium may be added to the discounted rate to compensate the seller. Again the buyer does not receive the net present value, but something less than the real value.