On second thought, I don't care about mega-efficient prints. If I
truly did, I would record the length of the last countdown and then fill
in just the gap, if any. A positive gap, that is, meaning the older
message was longer. But that's not worth it. If somebody piped this
output to a file, they probably should not have in the first place. It's
not what this script was designed for. One could always still use the
`-q` or `--quiet` flags. I reckon, that's better suited. But even then.
Simply don't do it.