Whether it’s your website or a clients it’s important to have responsible practices for WordPress backups.
You need to be proactive about backing up your WordPress website. Do not not rely on the chance that nothing will go wrong.
Ideally you want to choose a web hosting supplier who has backups built into their service. My recommendation is to always look for WordPress specific packages where possible. They typically have other WordPress specific optimisations as well as good backup offerings.
My current suggestion if you’re UK based would be Krystal’s managed Onyx platform.
However, where your web hosting provider doesn’t offer backups then use a plugin to send automated backups to remote storage.
Using remote storage is essential so your backups aren’t tied to your web sever should a failure occur. You don’t want to loose everything should the worst happen.
I’ve had success with UpdraftPlus and Dropbox when needed. The UpdraftPlus plugin allows you to backup both the database and files which is important.