diff --git a/mini-lsm-mvcc/src/compact/tiered.rs b/mini-lsm-mvcc/src/compact/tiered.rs
index 56ace89..4059078 100644
--- a/mini-lsm-mvcc/src/compact/tiered.rs
+++ b/mini-lsm-mvcc/src/compact/tiered.rs
@@ -90,7 +90,8 @@ impl TieredCompactionController {
                         .take(id + 1)
                         .cloned()
                         .collect::<Vec<_>>(),
-                    bottom_tier_included: id + 1 >= snapshot.levels.len(),
+                    // Size ratio trigger will never include the bottom level
+                    bottom_tier_included: false,
                 });
             }
         }
diff --git a/mini-lsm/src/compact/tiered.rs b/mini-lsm/src/compact/tiered.rs
index 56ace89..4059078 100644
--- a/mini-lsm/src/compact/tiered.rs
+++ b/mini-lsm/src/compact/tiered.rs
@@ -90,7 +90,8 @@ impl TieredCompactionController {
                         .take(id + 1)
                         .cloned()
                         .collect::<Vec<_>>(),
-                    bottom_tier_included: id + 1 >= snapshot.levels.len(),
+                    // Size ratio trigger will never include the bottom level
+                    bottom_tier_included: false,
                 });
             }
         }