Mitsu was in the same place as Subaru a while ago - finding their identity. Having one as a car maker can lead to success. Subaru found their mojo in AWD and the "Utility Wagon" concept then into CUVs and lots of hatches, etc. They gave a a range of cars, but not too broad, and included some badass stuff like the STi, etc. Then they hired some REALLY GOOD marketing people.
Mitsu lost their way, wandered around, and didn't build a cohesive product line based on a corporate identity. Marketing? What? Someone at Mitsu thought "that's a waste of money!"
In the end, it didn't matter really whether the cars were any good or not, no one knew to even look.