The Runs tab lists every time a workflow ran — one row per run — so you can see what happened each time it fired, not just the current state. It sits next to Activity in the workflow's nav.
The runs list
Each run shows:
Trigger — what started it (a schedule, an event, or a manual run).
Records — how many records the run enrolled and processed.
Status — how the run is going or how it finished.
Started — when it ran.
The list updates while you're watching it, and test runs (from an unpublished draft) are flagged as such.
Drill into a run
Click any run to open its own Activity view — the same record-by-record table as the Activity tab, but scoped to just that run. It's the fastest way to answer "what did last night's run actually do?" without the other runs' records mixed in.
Runs vs. Activity
Activity shows every record across the workflow, all runs together.
Runs breaks that down per run, so you can compare one firing to the next or investigate a single run in isolation.