Ask HN: What is the threat model of secure boot?

I am using Fedora on my laptop, which does not allow hibernate if secure boot enabled. It makes sense, but I am tired of finding my laptop out of charge on Monday morning, so I am disabling secure boot. The problem is, how damaging is this? I understand the point of secure boot, but if I check checksum of every fedora update and assume my laptop won't be physically touched by un-trusted, will there be still harm?