There used to be a large bike locker there. It was in the middle of the drive-through space you can see in the picture below:
The locked bike park is an "end of trip facility" along with things like lockers, changing rooms and showers which are meant to encourage more people to cycle. Sure enough, when I visited the hospital, I saw a couple of nurses ride out on mountain bikes after finishing their shift, dressed in lycra shorts and sporting a helmet, gloves and goggles as if they were preparing for a spot of mig-welding.
I must confess I have never been entirely convinced by the argument that it is end of trip facilities that will suddenly change cycling's modal share. I certainly do not agree that showers and changing rooms are needed. Unless people are actually training, cycling should really not be any more strenuous than walking and I have never heard it suggested that showers and changing rooms are needed to encourage people to walk to work. In the same way, I think calling for showers and changing rooms merely reinforces the (wrong) view that riding a bike is some sort of extreme sport requiring special equipment. The only special equipment it does need is safe routes.
I could of course be wrong. Generally there is a good number of bikes parked in the lock up. However given the number of doctors, nurses and other staff members that work at the Women's and Children's at any one time, it may not actually be that many at all.
Bike racks by themselves do not encourage cycling and neither, if you ask me, do end-of-trip facilities like showers and changing rooms. If you really want to encourage your employees to ride a bike to work, I think you need three things:
1. Easily accessible undercover bike parking and plenty of it;
2. An uninterrupted network of decent separated bike paths leading to it (something obviously the responsibility of local authorities rather than employers);
3. A little bit of information telling people about the network once its complete.
The bike park at the Women's and Children's is obviously meant for staff members and rightly so. Decent bike parking for visitors would be useful but a hospital is really not the place for making it difficult for people to arrive by car and charging them through the nose for the privilege of parking. If cycling were made pleasant so people had a genuine choice, you would not need to do anything that discouraged car use. I'm fairly sure people would just make the most rational choice depending on their needs at the time.
By the way, when I talk of decent bike paths, I do not mean this sort of garbage:
Taken in George Street, Norwood. That Holden is legally parked whatever the time of day.