Yes, they do, and in some respect, that’s the most important reason to keep your site updated. If your website crashes and you go out of business that’s bad enough, but if your site is compromised and hackers access client information – you can be criminally liable.
The number of attacks on sites worldwide is on the increase, and WordPress is the most popular system, so you absolutely need to protect the security of your passwords, details and all information on an ongoing basis. Website maintenance and updates help prevent all of that.