The thing is that motivation is not something people compare to some known value, but rather between people. If you hear that people were unmotivated from an enthusiastic/workaholic person it doesn't mean that they really were unmotivated. Just less motivated than this person.

Some of us are happy with working at a steady pace without many external symptoms of exctitation. I even believe this is better in the long run, people don't burn out and are better-rested.