I have been in hospitals where there is a lot of animosity between lab and nursing staff, and I was a point of care coordinator at a prior system and had a lot of experience on the lab side of things. I think that everything comes down to two main issues: bad apples and frustration.
Frustration is the less controversial topic. Simply put nursing staff get frustrated when they have a patient rapidly deteriorating who have sent a EDTA tube for a CBC 3 times, and every time they hear that it is clotted. You can replace this with most of the lab tests we run and nurses very quickly are pushed to their wits end. This builds up day after day, patient after patient. This is not the labs fault in any way, but is a huge cause of stress for nurses.
Bad apples are the more difficult topic, and many will want to argue that this doesn't exist (it does, both in the lab and in nursing). I have had lab techs give me the most inane excuses for why the sample will not work. I have been told that my EDTA tube was hemolyzed so that they could not run the CBC (wait it gets worse) but they were able to result the chem panel from a SST on the same draw. I have been told that my urine sample opened up in the tube system when I had personally walked the sample up to the receiving desk ( I have been told the same thing for CSF, which I will never send through a tube system). I have had countless draws where I was told that the sample was hemolyzed but I still had a tube from the same draw for POC testing and wasn't the least bit hemolyzed.
I never worked for the lab, but I do remember getting a phone call from one of our POC sites and they wanted me to push through a sample that was so far out of the QC parameters for the machine that it wouldn't even populate a result for half of the indicies, the patient had no prior testing, and "I think it just clotted" when I asked if there was enough for me to plate the next day to make sure the sysmex wasn't acting up. I can't imagine getting those phone calls on a daily basis, and I would be willing to bet that the lab hears these kids of excuses just as much as we get them.
If a sample was dropped, I'd rather just be told that the sample dropped. If a machine is broken and the samples are being sent out to another facility, please tell me (a TAT of 3 hours for an ETOH level is sooooo frustrating)! If I'm told a sample is hemolized so I ask for a tech to come collect it, it's not because I'm being lazy or retributionary but rather I truly don't think I can collect the sample, so please don't scoff at me.
From the nursing side I wish people wouldn't take shortcuts. I had to hear about how our POC strep rates were dropping compared to cultures, but the collecting provider or nurse barely touched one tonsil. Or would collect a viral panel on a flocked swab and barely go just enough to no longer see the swab on only one side of the nostril. Or seeing a clot come out of a syringe and have it still put into EDTA tube, like why do you think this would ever work for a CBC !?!