Senior/Principle/Staff/etc titles are typically less about raw competence or tenure and more about leadership. A senior will typically spend most of their time

Senior/Principle/Staff/etc titles are typically less about raw competence or tenure and more about leadership. A senior will typically spend most of their time working on high level design and overall strategy for a project, with execution left to more junior engineers. Seniors should be technical enough to jump in if necessary and they should guide junior engineers as needed but execution is not the main focus of the role.