[DjGilcrease]

Don't tell the Owners their money went to waste, but explain to them exactly what you posted here and let them decide to chase the sunk cost fallacy or not.

Without knowing more about the exact nature of the problems with the software you are having I cannot make a recommendation either way from a software development perspective.

I will however say many consulting development companies will continue to promise they will deliver while continually bringing in change orders to the original statement of work "Because 'this' situation was not covered in the original SOW"

If you find the company doing more then 1, maybe 2, small change orders as things evolve in a project of 9-12 months I would just drop them as that tells me they did not properly study the problem and ask the correct questions in order to properly do a SOW, that is unless things in the project are actually changing rapidly / dramatically from the original RFP.