Don't throw good money after bad is an idiom that is used to tell you not to waste more resources like time or money in a project or investment that is failing, just because you have already invested a lot.
You would use this idiom to give advice to someone to stop what they are doing.
You would use this idiom to give advice to someone to stop what they are doing.
Nobody is going to buy that product, you need to stop development on it. Don't keep throwing good money after bad.