This would be excellent advice for everyone. However, I'm also going to add that if you're using WHM (I haven't seen the options for Cpanel), there's a backup configuration that can be configured to automatically send daily server backups to an Amazon S3 account, then configure lifecycle rules, versioning rules, etc on the S3 side so you have continuous backups of your hosting reseller or VPS account remotely. I have backups going back a solid 12 months. These are daily, weekly and monthly. I then have lifecycle rules that push all backups over 30 days to Amazon Glacier and expire them out after one year. If you think it takes hours to set this up, it took me a grand total of about 15 minutes. That 15 min was well spent knowing my backups are transferred offsite every morning at 2am.
Always, always have your own backups and use some scripting to try and automate the process to off-site your own backups so you don't have to remember to download your own server backups. At the end of the day, we're all human.
Are you on a VPS? I've seen this in WHM on various VPSs, but I don't see those options in WHM as a reseller. Would be great to be able to take advantage of those backup options there.