Performance & battery · Measuring Storage Studio's own footprint
Why do I see more than one Storage Studio process in Activity Monitor?
Short answer: Storage Studio runs the menu bar app plus a small background helper that handles automatic tasks, so Activity Monitor lists both. It's normal; use Pause or Stop Service in the popover rather than force-quitting.
Storage Studio has two parts: the menu bar app you see, and a small background helper that runs its automatic tasks (scheduled moves and clean-ups) and starts at login. Activity Monitor lists them separately. That's normal.
Please don't force-quit the helper — automatic actions stop until it's running again. If you want everything to stop for a while, use Pause in the menu bar popover, or Stop Service if you want the background helper itself switched off; Start Service brings it back.
You can see the live status of each part in Settings → Services. More in the Preferences section of the manual.