diff --git a/app/src/main/java/eu/darken/capod/monitor/core/battery/CaseCharges.kt b/app/src/main/java/eu/darken/capod/monitor/core/battery/CaseCharges.kt
index cbc8ece7..95f0822b 100644
--- a/app/src/main/java/eu/darken/capod/monitor/core/battery/CaseCharges.kt
+++ b/app/src/main/java/eu/darken/capod/monitor/core/battery/CaseCharges.kt
@@ -28,6 +28,8 @@ data class CaseCharges(
  * makes a claim; anything straddling it is [CaseCharges.Adequacy.UNCERTAIN]. That also absorbs the
  * bounce between adjacent readings, so no state has to be remembered between frames.
  *
+ * The interval excludes its upper end, so an upper end of exactly one charge is still short of one.
+ *
  * A spec that is itself a lower bound has no upper end, so it can never claim "not enough".
  *
  * Null when the model publishes no case figures or the reading is missing or nonsense — the caller
@@ -44,7 +46,7 @@ fun caseCharges(spec: PodModel.CaseSpec?, reading: BatteryReading?): CaseCharges
     val adequacy = when {
         lowest >= 1f -> CaseCharges.Adequacy.ENOUGH
         spec.isLowerBound -> CaseCharges.Adequacy.UNCERTAIN
-        highest < 1f -> CaseCharges.Adequacy.NOT_ENOUGH
+        highest <= 1f -> CaseCharges.Adequacy.NOT_ENOUGH
         else -> CaseCharges.Adequacy.UNCERTAIN
     }
 
diff --git a/app/src/test/java/eu/darken/capod/monitor/core/battery/CaseChargesTest.kt b/app/src/test/java/eu/darken/capod/monitor/core/battery/CaseChargesTest.kt
index 4a2118e6..1a763afe 100644
--- a/app/src/test/java/eu/darken/capod/monitor/core/battery/CaseChargesTest.kt
+++ b/app/src/test/java/eu/darken/capod/monitor/core/battery/CaseChargesTest.kt
@@ -64,6 +64,15 @@ class CaseChargesTest : BaseTest() {
         charges(exact, 0.20f, percent)!!.adequacy shouldBe CaseCharges.Adequacy.NOT_ENOUGH
     }
 
+    @Test
+    fun `an interval ending exactly on one charge is not enough`() {
+        // the top of the interval is excluded, so 5.0 x (0.10 + 0.10) = 1.0 is still short
+        charges(PodModel.CaseSpec(fullPairRecharges = 5.0f), 0.10f, decile)!!
+            .adequacy shouldBe CaseCharges.Adequacy.NOT_ENOUGH
+        // 4.0 x (0.24 + 0.01) = 1.0
+        charges(exact, 0.24f, percent)!!.adequacy shouldBe CaseCharges.Adequacy.NOT_ENOUGH
+    }
+
     @Test
     fun `an interval straddling one charge claims nothing`() {
         // 4.0 x 0.20 = 0.8, 4.0 x 0.30 = 1.2