The Saturn L-Series wasn't necessarily bland as it was cheap and had a number of quality issues. Early Ecotec engine timing chains, electrical issues, suspension/alignment quirks. After a couple years they weren't so bad but the design didn't age well, especially given everyone else had redesigned their midsize sedans in '02/03.
I actually recently drove a Sentra of that era equivalent to the 200SX. Yeah, didn't really leave an impression. Might have been interesting in SE-R trim with the SR20 engine, but the most boring looking of the '90s small coupes.
This Infiniti M was probably more quickly forgotten:
Don't think anyone's really forgotten about the Forenza yet - they seem to have moved a good bit of them since they were cheap. The Reno hatchback equivalent though, that's all but forgotten. Probably the Verona sedan was more easily forgotten than either:
(So wait, do we count this as a predecessor of the new Malibu now?

)
Hitman1970 said:
We practically bought a Five Hundred with the 2005 Freestyle for my wife. If the Five Hundred was forgettable how come the Passat that it cloned was not?
Forgettable not just for styling (even if they didn't really put that in the list). Passat was well-received by the media when it came out. Five Hundred with the same old Duratec V6 didn't stand a chance against the also-new Chrysler 300...
That said I did really like the Five Hundred and its equivalents for all the space inside. The '08 Taurus was odd looking; the '10 looked good but lost that spacious feeling.