Strange GCE PV/PVC behaviour

gistfile1.txt

$ gcloud compute disks list
NAME                                 ZONE            SIZE_GB  TYPE         STATUS
disk100-001                          europe-west1-d  100      pd-standard  READY
gke-unrest-micro-pool-199acc6c-3p31  europe-west1-d  100      pd-standard  READY
gke-unrest-micro-pool-199acc6c-4q55  europe-west1-d  100      pd-standard  READY

$ kubectl get pv
NAME             CAPACITY   ACCESSMODES   STATUS    CLAIM                           REASON    AGE
pv-disk100-001   100Gi      RWO           Bound     default/graphite-statsd-claim             2m

$ kubectl get pvc
NAME                    STATUS    VOLUME           CAPACITY   ACCESSMODES   AGE
graphite-statsd-claim   Bound     pv-disk100-001   0                        3m

$ kubectl describe pvc
Name:		graphite-statsd-claim
Namespace:	default
Status:		Bound
Volume:		pv-disk100-001
Labels:		<none>
Capacity:	0
Access Modes:

$ kubectl describe pv
Name:		pv-disk100-001
Labels:		<none>
Status:		Bound
Claim:		default/graphite-statsd-claim
Reclaim Policy:	Recycle
Access Modes:	RWO
Capacity:	100Gi
Message:
Source:
    Type:	GCEPersistentDisk (a Persistent Disk resource in Google Compute Engine)
    PDName:	disk100-001
    FSType:	ext4
    Partition:	0
    ReadOnly:	false

# Events for pod that is supposed to mount this volume:
Events:
  FirstSeen	LastSeen	Count	From						SubobjectPath	Type		Reason		Message
  ---------	--------	-----	----						-------------	--------	------		-------
  6h		1m		183	{kubelet gke-unrest-micro-pool-199acc6c-4q55}			Warning		FailedMount	Unable to mount volumes for pod "graphite-statsd-1873928417-i05ef_default(bf9fa0e5-4d8e-11e6-881c-42010af001fe)": timeout expired waiting for volumes to attach/mount for pod "graphite-statsd-1873928417-i05ef"/"default". list of unattached/unmounted volumes=[graphite-data]
  6h		1m		183	{kubelet gke-unrest-micro-pool-199acc6c-4q55}			Warning		FailedSync	Error syncing pod, skipping: timeout expired waiting for volumes to attach/mount for pod "graphite-statsd-1873928417-i05ef"/"default". list of unattached/unmounted volumes=[graphite-data]

# Extract from deploy yaml file:
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-disk100-001
spec:
  capacity:
    storage: 100Gi
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  gcePersistentDisk:
    pdName: disk100-001
    fsType: ext4
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: graphite-statsd-claim
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi
---