What part of maintaining a website takes more time than it should?

Building a website gets a lot of attention, but I think the ongoing maintenance is where the hidden workload starts to show up.

Updates, performance checks, security, SEO, integrations, content changes, hosting issues — individually, none of these sound huge. But once you're managing multiple sites, the small tasks can add up quickly.

I'm curious how other makers and agencies experience this.

What part of maintaining a website consistently takes more time than you think it should?

And have you found a way to reduce that workload, or is it still something you mostly handle manually?