The most common item — that I do often — is to add tags to aid in search and discovery (the title edit button puts the title and tags field into edit mode).
If I split topics, I also have to create a title for the new post — which other regulars can then edit and improve.
This is a community space and we moderate, manage, and improve it together.
If you want to contribute you’re welcome to write a post in meta that becomes the FAQ and guide for this.
You can read the previous thread on this shortly after launch, although it was more focused on body edits than titles.