diff --git a/apps/api/src/jobs/prefetch-window-budget.spec.ts b/apps/api/src/jobs/prefetch-window-budget.spec.ts
index 44b82e6..a9702e0 100644
--- a/apps/api/src/jobs/prefetch-window-budget.spec.ts
+++ b/apps/api/src/jobs/prefetch-window-budget.spec.ts
@@ -164,6 +164,9 @@ describe("process() gate order — window before daily budget", () => {
 
     expect(job.moveToDelayed).toHaveBeenCalled();
     expect(dailyIncrs(incrCalls)).toHaveLength(0);
+    // The per-minute counter is not charged either: the window gate is pure
+    // clock arithmetic and runs before any Redis write.
+    expect(incrCalls).toHaveLength(0);
     // …and the handler never ran, so nothing was fetched upstream either.
     expect(categoriesService.getCategoryWithParts).not.toHaveBeenCalled();
   });
diff --git a/apps/api/src/jobs/prefetch-worker.service.ts b/apps/api/src/jobs/prefetch-worker.service.ts
index fb854e8..fcde616 100644
--- a/apps/api/src/jobs/prefetch-worker.service.ts
+++ b/apps/api/src/jobs/prefetch-worker.service.ts
@@ -355,23 +355,30 @@ export class PrefetchWorkerService implements OnModuleInit, OnModuleDestroy {
           job.name === "prefetch-parts")
       ) {
         const lane = (job.data as { fast?: boolean }).fast ? "fast" : "main";
-        await this.checkSourceRate(data.source, lane);
-        // Cooldown + business-hours window BEFORE the daily charge. These two
-        // gates used to live at the top of each handler, i.e. AFTER the budget
-        // was already debited, so every job that woke outside the window paid a
+        // GATE ORDER IS LOAD-BEARING — cheapest first, and every gate that can
+        // reject the job must run BEFORE any counter is debited.
+        //
+        // The business-hours window and the cooldown used to sit at the top of
+        // each handler, i.e. AFTER the per-minute counter and the daily budget
+        // had already been charged. So a job that woke outside the window paid a
         // budget unit to do nothing. Combined with a deferral target of "next UTC
         // midnight" (= 03:00 Europe/Istanbul, six hours before a 09:00 window
-        // opens) that formed a closed loop: the whole daily allowance was burned
-        // by no-op wake-ups before the window ever opened, so the source never
-        // ran again. Measured on prod 2026-09-20: pl24 at 600/600 with 0 catalog
-        // requests and 0 new categories for the day. Order matters here.
-        await checkCooldown(this.redis, data.source);
+        // opens) that closed a loop: the whole daily allowance was burned by
+        // no-op wake-ups before the window ever opened, so the source never ran
+        // again. Measured on prod 2026-09-20 — pl24 at 600/600 with 0 catalog
+        // requests and 0 new categories for the day.
+        //
+        // 1. Window: pure clock arithmetic, no I/O, and an out-of-window job can
+        //    never do useful work — so nothing else is worth spending on it.
         checkTimeWindow(data.source);
-        // Daily budget AFTER the per-minute gate: a job deferred on the minute
-        // ceiling above never reaches here, so rate-limited retries don't inflate
-        // the daily counter — only jobs about to do real work are counted. The
-        // lane decides which threshold applies (backfill stops at the main limit,
-        // the user's fast lane may use the full budget).
+        // 2. Cooldown: one Redis TTL read. Pauses the whole worker (see catch).
+        await checkCooldown(this.redis, data.source);
+        // 3. Per-minute ceiling.
+        await this.checkSourceRate(data.source, lane);
+        // 4. Daily budget last: a job deferred on any gate above never reaches
+        //    here, so only jobs about to do real work are counted. The lane
+        //    decides which threshold applies (backfill stops at the main limit,
+        //    the user's fast lane may use the full budget).
         await this.checkSourceDailyBudget(data.source, lane);
       }
       if (data.source === "parts-catalogs" && PCAT_PACE_MS > 0) {