We have too little information to really make any kind of an informed decision.
Here is what we know:
A vehicle was parked where it typically would not be. The authorities were informed and the response was not "timely".
Here's what we don't know (only given what Chris typed in his OP):
How did the caller (neighbor) describe the car? was it "suspicious"? was it described as "abandoned"? Was it newer and well cared for? Was it a heap of junk and likely to have broken down? Did it have an obvious issue that went undiscovered (flat tire on the side away from viewpoint)?
We will presume that whomever called in the initial concern, didn't call back and say "never mind; it's gone now", or the cops would not have made the effort, however late. Why didn't the caller call back and say "Hey - don't waste any time here; the concern is gone". You see, if he had done that, it would have freed up the time the officer did expend to show up. Now multiply that by all the other "GOA" (Gone upon my arrival) calls.
Additionally, as Mola stated, there are priority of call issues here. Do any of us know the specific protocol and heirarchy of the department in question here??? I doubt it. And was the call properly categorized initially?
Finally, there are the IT issues that do happen. Perhaps the call got put into the cue correctly, but the computer system glitched? It has personally happened to me. I was on a traffic stop right near the end of my shift a few years ago. I cleared the call on the MDT (mobile data terminal) in my car. I logged off the computer after a few minutes and then went home, showered and went to bed. A few hours later there was a knock at my door around 0200 hrs. The local cops (not the same department as which I serve) were sent out to see if I was at home. Seems the computer had "stalled" (my term) my call and after several hours it popped back up and resurfaced in the CAD (computer aided dispatch) system. The dispatchers were freaking out because it showed me out on a traffic stop location that now was physically empty. My bros in blue were panicked when they could not find me, nor the car. This is because a shift change had occurred and the night shift didn't know that I'd already cleared the call. So my point is that things can happen electronically; computer systems are not perfect just as humans are not. The call may have been stalled in the responding agency systems for some unknown reason; the late response may not have been due to human issues.
In the end, all we're left with here is too little information and too much conjecture.