If your website disappeared today, could you reconstruct it from memory? I couldn't. What would you lose if it was totally gone, forever? Now, that's unlikely to ever happen. Still, I sleep better at night knowing that if something were to happen to our website and all our clients' websites, we would be able to reconstruct them.
Yes, your hosting company should have a backup, and so should your web designer, but they are not obligated to bail you out if your site is deleted or destroyed. You need to take responsibility for keeping backups of not only your website, but everything else that is of value to you like your graphics, images, and the information you put online. We backup everything we do onto secure cloud storage AND onto an external hard drive. Important files are password-protected and remain so in the backups. If one fails, we have the other.
I've used various software to do website backups and have used manual backups as well (ugh). I think an automated service or app is the best way to go. I've got better things to do than spend a whole day every month making backups. One of the best I've found is top-rated SiteSucker. It's for Mac's and available from the Mac App Store for $5. (If you have a PC, see below for more info.) I use it monthly to backup ALL the websites we have created or work on, so if you're a client, know that I've got a backup of your site. It takes me, oh, 30 minutes to back up dozens of websites. Easy peasy.
If you change your site daily or even weekly, it might be worth the investment to have an automated service that backs up your website daily. CodeGuard* is one, prices start at $5/month for one website, and you can add up to 10 websites for an additional $5/month per site. (*Works with custom sites and WordPress. If you have a template site check with that company or do the free trial to make sure it's going to work.) You can use this no matter what type of computer you have.
If you have a webmaster, you can always ask them how much it would cost to backup your website and send you the files.