diff --git a/backend/src/main/java/org/raddatz/familienarchiv/relationship/RelationshipInferenceService.java b/backend/src/main/java/org/raddatz/familienarchiv/relationship/RelationshipInferenceService.java
index bc820e6f..7191c222 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/relationship/RelationshipInferenceService.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/relationship/RelationshipInferenceService.java
@@ -20,6 +20,9 @@ import java.util.*;
 @RequiredArgsConstructor
 public class RelationshipInferenceService {
 
+    // 8 hops covers great-grandparents ↔ great-great-grandchildren and second cousins —
+    // the practical horizon for a 1899–1950 family archive. Paths longer than this are
+    // classified as LABEL_DISTANT and rarely carry meaningful relationship labels.
     static final int MAX_DEPTH = 8;
 
     /** "distant" is the catch-all label for paths that do not match the LABEL_MAP. */