In some contexts is unclear why an autoscaling policy decides to request
more resources, i.e. if there's an unassigned shard that remains unassigned
even after adding more resources. It would be help to have more information
around the decisions taken by the deciders so it is easier to understand and
track them.
x-pack/plugin/autoscaling/src/test/java/org/elasticsearch/xpack/autoscaling/storage/ReactiveStorageDeciderDecisionTests.java
++round;
        }
        assert round > 0;
        assertThat(state, sameInstance(lastState));
    }
    public void testStoragePreventsMove() {
        
        
        
        allocate();
        
        Set<ShardId> warmShards = Sets.union(new HashSet<>(randomSubsetOf(shardIds(state.getRoutingNodes().unassigned()))), subjectShards);
        
        withRoutingAllocation(
            allocation -> RoutingNodesHelper.shardsWithState(allocation.routingNodes(), ShardRoutingState.INITIALIZING)
                .stream()
                .filter(ShardRouting::primary)
                .filter(s -> warmShards.contains(s.shardId()))
                .forEach(shard -> allocation.routingNodes().startShard(logger, shard, allocation.changes()))
        );
        do {
            startRandomShards();
            
        } while (StreamSupport.stream(state.getRoutingNodes().unassigned().spliterator(), false)
            .map(ShardRouting::shardId)
            .anyMatch(warmShards::contains));
        
        withRoutingAllocation(
            allocation -> RoutingNodesHelper.shardsWithState(allocation.routingNodes(), ShardRoutingState.STARTED)
                .stream()