diff --git a/README.md b/README.md
index 0f94dc3..1a5d0dc 100644
--- a/README.md
+++ b/README.md
@@ -40,6 +40,11 @@ either "On Foot" for Odyssey, or "Ship" for regular ones. Then select the grade
 high), and how many you won. Then press "Accept". Select "Cancel" to abort. You can of course remove
 the combat zone entries by selecting them, and pressing "DEL".
 
+If you deliberately fail a mission (to log negative INF towards a faction), the tool cannot detect
+it, if the day you accepted the mission is outside of the given date range. It needs the journal
+entry where you accept the mission to connect the mission to a faction, system and station. The tool
+will warn you if this happens, with a message in the error log in the fourth tab.
+
 ![Main Window with entries](main-entries.png)
 
 The window will then list all the journal entries it has found, and group them by objectives. You