Can bash echo command return non-zero exit code?

Nope, no risk. From man bash:

echo [-neE] [arg ...]
Output the args, separated by spaces, followed by a newline. The return status is always 0. If -n is specified, the trailing newline is suppressed. If the -e option is given, interpretation of the following backslash-escaped characters is enabled. The -E option disables the interpretation of these escape characters, even on systems where they are interpreted by default. The xpg_echo shell option may be used to dynamically determine whether or not echo expands these escape characters by default. echo does not interpret -- to mean the end of options. echo interprets the following escape sequences:

Emphasis on "The return status is always 0".

From a code quality standpoint, I would recommend not using test unless you're forced to for shell compatibility reasons. In general, use [[, but for arithmetic expressions you can also use ((:

# The generic way[[ $retry_counter -eq 0 ]] && echo "Thing didn't happen" && exit 1# The arithmetic way(( retry_counter == 0 )) && echo "Thing didn't happen" && exit 1

Yes, echo has a non-zero return status if there's a write error.

Quoting the bash manual:

'echo'

echo [-neE] [ARG ...]

Output the ARGs, separated by spaces, terminated with a newline. The return status is 0 unless a write error occurs.

A demonstration:

$ cat foo.bash#!/bin/bashecho helloecho "The echo command returned a status of $?" > /dev/tty$ ./foo.bash > /dev/full./foo.bash: line 3: echo: write error: No space left on deviceThe echo command returned a status of 1$ 

/dev/full is a device, similar to /dev/zero except that any attempt to write to it will fail with an ENOSPC error.

From help man (bash):

Exit Status:

Returns success unless a write error occurs.

UPDATED

So if you echo to a stream that suddenly fails, you will get another exit code.