“Throw good money after bad” (to waste additional money)
“To throw good money after bad” is to further invest in a losing venture. If much money has already been sunk into the venture—General Motors, for example—a “bailout” of fresh money might save the company, or the bailout might lose even more money by “throwing good money after bad.”
The phrase “throw good money after bad” was a proverbial phrase by at least 1662.
Answers.com
Idioms: throw good money after bad
Waste more money in hopes of recouping previous losses, as in Hiring him to improve that software is throwing good money after bad; it’s based on an older operating system and will soon be obsolete. [Late 1800s]
The Free DIctionary
throw good money after bad
Fig. to waste additional money after wasting money once. I bought a used car and then had to spend $300 on repairs. That was throwing good money after bad. The Browns are always throwing good money after bad. They bought an acre of land that turned out to be swamp, and then had to pay to have it filled in.
(Oxford English Dictionary)
to throw good money after bad and variants: to incur a further loss in trying to make good a previous one
1662 G. TORRIANO Proverbial Phrases 197/1 The English say, To send good Mony after bad, to lose the Substance, for the Shaddow.
1690 W. FITZHUGH Let. 8 Aug. in R. B. Davis William Fitzhugh & his Chesapeake World (1963) 294 More money would be spent on prosecuting than he would be able to answer, & consequently good money thrown after bad.
1792 J. BELKNAP Foresters xii 149 Why should I keep on throwing away good money after bad; I am damnably in debt now.
1823 H. LUTTRELL Crockford-House ii. 93 Mighty Man of cards and dice, Take a real friend’s advice… Don’t, or I shall think you mad, Throw good money after bad.
Google Books
A review of the affairs of France: and of all Europe, as influence’d by that nation
London
1705
Pg. 428:
As he owns the Debt was but small, they think he is but rightly serv’d for going to Law for a Trifle, and throwing good Money after bad.
Google Books
An apology for the life of Mr. Colley Cibber, comedian, and late patentee of the Theatre-Royal. With an historical view of the stage during his own time
By Colley Cibber
London: Printed by John Watts for the author
1740
Pg. 278:
...in not throwing away good Money after bad, this Hero of a Menager, who alone supported the War, should in time so fortify himself by Delay, and so tire his Enemies, that he became sole Monarch of his Theatrical Empire, and left the quiet Possession of it, to his Successors.