pico doesn't go with Centos.
As result you can get something like the following:
crontab -e /bin/sh: pico: command not found crontab: "pico" exited with status 127
To get rid of this error, do the following:
Install nano editor if needed:
yum install nano -y
And run:
cd /usr/bin/ ln -s nano pico export EDITOR="pico"