Apps · Offloading and restoring apps
What does "Tried once and it didn't work" mean when offloading an app?
Short answer: An offload attempt failed and the reason is shown. One failure is often temporary, so you can retry; if it repeats, Storage Studio says the app can't be offloaded on this Mac. Nothing is changed.
It means an offload attempt for that app didn't succeed, and Storage Studio is telling you why. A single failure is often temporary — the app was busy, the drive was briefly unavailable — so the Offload button stays and you can try again.
If the same app fails again, Storage Studio says "This app can't be offloaded on this Mac" with the reason. Either way nothing was changed. You can use Move or Uninstall instead.