The primary objective was always planned to last few days, and it did that part pretty much perfectly (80-90% of results were received). After these few days, t

The primary objective was always planned to last few days, and it did that part pretty much perfectly (80-90% of results were received). After these few days, there was a secondary objective, which was to turn Philae into a kind of weather station on a comet, with pretty much every instrument turned off. It would have been great if it had worked of course, but compared to the main objective it doesn't really matter. What they really want to know is the chirality of the water on the comet and wether or not the comet contains certain elements, it seems like they manage to get this data. Also the secondary objective is not totally abandonned, since there is still a chance to see Philae back in some months, with the comet getting much more sunlight and warming considerably. Plans change with time, and the FAQ is adapted to those plan. Hell iirc there wasn't even suppose to be a lander in there initial plan 25 years ago.