TiME is a seafaring probe designed to explore the lakes and seas of Saturn's moon Titan's. So why didn't NASA launch it?

On 22 July 2006, lakes and seas were discovered on Titan, Saturn's largest moon. These are located in Titan's northern hemisphere. The discovery confirmed the hypothesis that liquid hydrocarbons exist on Titan. Most of Titan goes centuries without seeing any rain, but precipitation is expected to be much more frequent at the poles.

Titan Mare Explorer (TiME) was designed to land on Titan and would have performed the first nautical exploration of an outer space sea. It was to analyse the nature of the seas and explore the shorelines. The target lake was Ligeia Mare (78°N, 250°W). It is one of the largest lakes of Titan identified to date, with a surface area of about 100,000 km2.

TiME was one of three Discovery Mission finalists that received US $3 million in May 2011 to develop a detailed concept study. The other two missions were InSight and Comet Hopper. After a review in the Summer of 2012, NASA announced in August 2012 the selection of the InSight mission to Mars.

The chance to discover a form of life with a different chemical basis than life on Earth has led some researchers to consider Titan the most important world on which to search for extra-terrestrial life.

(Source)