Is there a cleaner way of getting the last N characters of every line?

Question

To simplify the discussion, let N = 3.

My current approach to extracting the last three characters of every line in a file or stream is to use sed

Answer 1

Pure bash solution:

$ while read -r in; do echo "${in: -3}"; done
hello
llo
$

sed

$ sed 's,.*\(.\{3\}\)$,\1,'
hallo
llo
$