There were several, perhaps dozens from many countries but I narrowed it down to two rather notorious aircraft, one produced by Brewster and one by Curtiss for the U.S. Navy during WWII.

The Brewster SB2A was a dive bomber design with several advanced features. Delayed by labor and quality control issues at the Brewster factory coupled with lackluster performance, relegated this once promising design with a full slate of export orders to use as target tugs and maintenance trainers. Incredibly nearly 500 were built but none ever saw combat. The US had trouble giving them away to Great Britain. The U.S. Navy used them to test catapults, shooting brand new aircraft into the ocean. 

The Curtiss SO3C Seamew was a monoplane floatplane designed to replace another Curtiss design, the biplane SOC Seagull. The Seamew was plagued with the stability issues and water handling difficulties. Rather than try to fix its issues it was easier for the Navy to just put the SOC Seagull back in service. The Royal Navy used the Seamew briefly, replacing the floats with fixed landing gear, but declared them surplus to requirements before initial deliveries were even complete.