Two things control whether a user can change or delete a report: their role's Report Permissions, and whether they're an owner of the report. Administrators can always change any report.
Report Permissions in User Roles
Go to Settings > User Roles, then select the role.
Under Reports, set Report Permissions:
None: users can't open Reports and can't be made an owner of a report.
Read: users can open reports shared with everyone and reports they own, but can't create or change a report.
Full: users can create reports and change the reports they own. Reports shared by others are read-only to them.
Save the role.
Report ownership
A user with Full report permissions can only change, share, or delete reports they own. To let someone maintain a shared report, an owner or Administrator adds them as an owner in Configure Report > Sharing and ownership. To stop someone from changing a report, remove them as an owner.
In short:
To let a user view reports but never create or change them, set their role to Read.
To let a user build their own reports but not change shared ones, set their role to Full and don't make them an owner of shared reports.
Learn more in Who Can View, Edit, and Schedule Reports and Sharing and Owning Reports.
What's Next?
Looking for information regarding User Roles? Check out our guide below!