I have a trigger defined like this:

if [[ "$(p4 -Ztag -F %desc% describe -s $1 2>&1)" =~ ^([(Misc|Bug-Dev|Bug-Live|Feature|Public)])+ [a-zA-Z0-9]+.* ]]
then
    exit 0
else
    echo $1
    echo $(p4 -Ztag -F %desc% describe -s $1 2>&1)
    echo "Nothing"
    echo " Invalid commit message"
    echo " Expected commit message format:"
    echo "  [Type] Message"
    echo " where there can be multiple tags of Type:"
    echo "  Misc|Bug-Dev|Bug-Live|Feature|Public"
    exit 1
fi

Running command p4 -Ztag -F %desc% describe -s $1 2>&1 on my local machine works without issues, I get the submit message.

However, if I try to submit anything, I get the following result:

Notice that the line where the output of echo $(p4 -Ztag -F %desc% describe -s $1 2>&1) would go is empty.

What is going on here?