Cost more than the Mondeo, sat on the same platform as a Mondeo, drove the same as the Mondeo, was less practical than the Mondeo, had less power than the Mondeo, and ended up being sold alongside the newer (and better) Mondeo III.
In America, it had all the same problems, except instead of being sold alongside the Mondeo III (which we never got) it had the unfortunate task of trying to combine MN12 Mercury Cougar owners with Ford Probe owners for its target demographic by using the questionable sales strategy of alienating both of them.
It essentially failed for the same reason that all mid-sized FWD luxury coupes fail.