Would You Adam and Eve It?

Been watching a Robin collecting grass or moss and disappearing in the same direction every time so I went on a nest hunt. Now, there is a perfectly good, safe, dry nest box on the back of the shed set up for any Robin looking for a des res:

   

As can be seen from the grab from the video camera inside the box, completely deserted.
Anyway, that wasn't the direction the Robin kept disappearing. That was almost to ground level at the side of the greenhouse. What was there which would be of interest to a Robin?

An abandoned watering can?:


A quick peek inside showed some fresh moss near the back:


A closer view:


Yes, definitely signs of recent activity.
Now, is this going to be a safe place to bring up a family?
Too many cats prowling at all times of day and night so we will have to wait and see what happens.
Maybe I could erect some wire netting to protect the area.

No problem with the can filling with water when it rains.
It was abandoned as there is a large crack in the base so it has good drainage.

Robins are well known for using anything they think suitable as a nesting site from kettles to cardboard boxes in outbuildings.