diff --git a/pageserver/src/tenant/timeline.rs b/pageserver/src/tenant/timeline.rs
index f7227efeba..b2183e8275 100644
--- a/pageserver/src/tenant/timeline.rs
+++ b/pageserver/src/tenant/timeline.rs
@@ -3243,7 +3243,9 @@ impl Timeline {
             // space. If that's not the case, we had at least one key encounter a gap in the image layer
             // and stop the search as a result of that.
             let mut removed = keyspace.remove_overlapping_with(&image_covered_keyspace);
-            // Do not fire missing key error for sparse keys.
+            // Do not fire missing key error and end early for sparse keys. Note that we hava already removed
+            // non-inherited keyspaces before, so we can safely do a full `SPARSE_RANGE` remove instead of
+            // figuring out what is the inherited key range and do a fine-grained pruning.
             removed.remove_overlapping_with(&KeySpace {
                 ranges: vec![SPARSE_RANGE],
             });