diff --git a/winnow/cache.py b/winnow/cache.py
index b3ebf7d..6ce3126 100644
--- a/winnow/cache.py
+++ b/winnow/cache.py
@@ -90,7 +90,7 @@ class EmbeddingCache:
             np.save(tmp, embedding)
             os.replace(tmp, final)
         except Exception as e:
-            logger.debug("Cache write failed for %s: %s", asset_id, e)
+            logger.warning("Cache write failed for %s: %s", asset_id, e)
             try:
                 os.remove(tmp)
             except OSError:
diff --git a/winnow/executor.py b/winnow/executor.py
index 656148b..8d1c2f9 100644
--- a/winnow/executor.py
+++ b/winnow/executor.py
@@ -507,6 +507,7 @@ def upload_to_frigate(jobs: list[dict]) -> None:
 
                             asset_id = asset_map.get(fname)
                             if asset_id:
+                                tracker_ok = True
                                 try:
                                     mark_uploaded(
                                         asset_id,
@@ -516,6 +517,7 @@ def upload_to_frigate(jobs: list[dict]) -> None:
                                         frigate_score=pre_fscore,
                                     )
                                 except Exception as tracker_exc:
+                                    tracker_ok = False
                                     # Upload to Frigate succeeded — don't retry on tracker
                                     # failure or we'd upload a duplicate to Frigate.
                                     logger.error(
@@ -523,9 +525,10 @@ def upload_to_frigate(jobs: list[dict]) -> None:
                                         " but asset may be re-selected next run: %s",
                                         fname, tracker_exc,
                                     )
-                                if pre_fscore is not None:
-                                    person_has_fscores = True
-                                actually_uploaded.append((fname, asset_id))
+                                if tracker_ok:
+                                    if pre_fscore is not None:
+                                        person_has_fscores = True
+                                    actually_uploaded.append((fname, asset_id))
 
                             break
                         else:
diff --git a/winnow/jobs.py b/winnow/jobs.py
index 50706e8..3449883 100644
--- a/winnow/jobs.py
+++ b/winnow/jobs.py
@@ -70,6 +70,8 @@ def _resolve_strategy(strategy: str, has_embedding: bool) -> tuple[int | str, st
 
     custom_limit = _getenv_optional_int("LIMIT")
     if custom_limit is not None:
+        if custom_limit == 0:
+            logger.warning("LIMIT=0 selects zero images — set LIMIT to a positive integer or leave unset for auto")
         return custom_limit, "smart"
 
     strategy_map = {