In case you don't get a better answer (I've experiences with highline,
but not with 'echo'):

If you are on Windows, maybe it does not work.

If you are on Linux/Unix, do you have everything from the
documentation:

"
echo:
This requires HighLine√‘ character reader. See the character attribute
for details.

Note: When using HighLine to manage echo on Unix based systems, we
recommend installing the termios gem. Without it, it√‘ possible to
type fast enough to have letters still show up (when reading character
by character only).
"

-Axel