Understanding Bounded Queue Behavior in Effect Program

const program = Effect.gen(function*() {
  const queue = yield* Queue.bounded<string>(1);

  const receiver = yield* Effect.gen(function*() {
    yield* Effect.log("Receiving");
    const msg = yield* Queue.take(queue);
    yield* Effect.log("Received:", msg);
  }).pipe(Effect.repeatN(3), Effect.fork);

  const sender = yield* Effect.gen(function*() {
    yield* Effect.log("Sending X");
    yield* Queue.offer(queue, 'X');
    yield* Effect.log("Sending Y");
    yield* Queue.offer(queue, 'Y');
    yield* Effect.log("Sending Z");
    yield* Queue.offer(queue, 'Z');
  }).pipe(Effect.fork);

  yield* Fiber.joinAll([sender, receiver]);
});