It was something like:
- almost everybody only uses about 20% of the features of Word
- everybody's 20% is different, but
- ~80% of the 20% is common to most users.
- on the other hand, the remaining 20% of the 20% is widely distributed and covers basically all of the product.
So if you made a version of Word with 16% of its feature set you would almost make everybody happy. But really, nobody would be happy. There's no small feature set that makes most people happy.