I also work in a hospital, and my preferred parking spot is where I can pull through (so as to pull forward to leave when it's time to go home, as well). I have a lot more control over my arrival time (vs my start of the work day) so that I can arrive with plenty of time to get parked (especially considering I clock in at my desk, which is on the fifth floor, and it's always a gamble as to whether the elevator will go straight up or if I end up stopping at every floor). It's a lot safer to pull out forward from a parking spot, especially since it seems that everyone is leaving at the same time (and a whole lot more anxious to go home, driving like the proverbial bat-outta-hotspot. Not signaling intent when parking, though, is pretty rude.
I'm more reminded of what happened one morning--to come in, you drive on this road, stop at a stop sign and turn left. On the immediate right after that left turn is a double row of parking spots (thus, you can pull through if you are in time to get the first row) then a driving lane, and then several rows that are perpendicular to that first row. Now that first double row is my preferred parking area. It's actually fairly far from the entrance, but I can pretty much *always* get a spot there, which means that I don't have to think about where I parked when I am headed home (I have walked out with several co-workers who, on various occasions cannot remember where they parked because they don't have a particular spot that they ordinarily park in). One day, I followed another car in, and they turned almost immediately into the double row, I was headed for the other end of the double row when, all of a sudden, without signalling, that car had continued in through the perpendicular area to drive around one of the concrete "planter" ends (it is raised concrete, there's some ground in there with a rather anemic looking tree planted) to come back to the double row that I was about to park in (pulling back through the other way). I had to do some sharp maneuvering myself to avoid a collision. Fortunately, no one was immediately behind me.
Situational awareness is a good thing. Communicating your intentions (via turn signals) is a very good thing.
Whether someone pulls in and through, backs in (rim of the lot spots, in particular) or pulls in and needs to back out of the spot--well, the backing out tends to be not so safe just because you have impaired ability to see around other vehicles until you're well into the driving lane, but otherwise it's pretty much a matter of indifference to everyone.