Why "ever" instead of "always"?

[Semil]

English Language Tests, Intermediate level

ESL/EFL Test #708 "Ever vs. never", question 9

A: I might do that one day because I'm ......... willing to learn something new.

(a) sometimes
(b) ever
(c) always
(d) never

English Language Tests, Intermediate level

ESL/EFL Test #708 "Ever vs. never", answer 9

A: I might do that one day because I'm always willing to learn something new.

Correct answer: (c) always

Your answer was: incorrect
A: I might do that one day because I'm ever willing to learn something new.
_________________________

why "ever"instead of "always"?

semi