This was supposed to be a simple question, but not really Why Can't Medics Intubate? I guess I should have anticipated, based on a lot of experience with the topic, that the conversation would not go as planned.
What was the plan?
The plan was not to suggest that few medics can intubate well, or that no medics can intubate well. If there is a difficult prehospital airway, do not expect many anesthesiologists or emergency physicians to volunteer to place the tube. Except for those with an EMS background, these physicians will not be comfortable in this setting. Even in the airway seat of an ambulance, they will feel like fish out of water.
This is not a criticism of anesthesiologists or emergency physicians. When I am being critical of either, or both of them, I will try to make it clear.
Why work in a setting that is uncomfortable? This is something that some people have trouble learning. It was one of my many problems. Trying to prove that you can do something, regardless of the setting, is just a bad idea - and bad patient care. Get the patient to the place where you are most likely to be successful in placing the tube. If you mess around for 10 minutes, in the spot where you found the patient, is there any guarantee that you will place the tube? No. If you move the patient, there is still no guarantee, but you at least give the patient a better shot at a patent airway. And isn't that the goal?
Well, then why not just drop in a King LT, or LMA (Laryngeal Mask Airway), or CombiTube, or some other alternative airway?
No good reason not to. We just are not used to having these alternatives. I have worked places that only had BVM (Bag Valve Mask) and suction as airway alternatives. Other services had the EOA (Esophageal Obturator Airway) - all the problems of intubation and all of the problems of the BVM, but few of the benefits. Things have changed.
And I don't mean that adding RSI (Rapid Sequence Induction) is a new thing. Paramedic RSI has been around since the 1970s. 1970s and new do not belong in the same sentence.
One thing has not changed - medics identify themselves by the ability to intubate.
So why are so many medics so bad at intubation?
Wow! It is almost as if you can read my mind. That is what I was going for.
1. Most medics do not understand intubation anywhere near as well as they believe they do. They have often been taught by similarly limited medics.
2. Most medics are lazy. How often do you see them practicing with a mannequin, or even asking the boss to get a mannequin, so that they can practice? What about asking to get some cadaver lab experience? OR experience? Anyone?
I think the number of medics, who seek this practice is much smaller than the number of medics who can't intubate in these studies. Please provide me with some evidence, if you disagree. In the absence of evidence to the contrary, I maintain that most medics are lazy.
3. We do not know why we intubate.
Less than 8 intubate?
I need to protect the airway.
Dude, I have RSI. I intubate because I can intubate.
What if QA/QI/CYA looks at my chart and gigs me for not intubating the patient?
Well then, why should we be intubating?
We should only be intubating because we have evidence that it leads to better outcomes for the patient.
We can't even get research that shows that medics can intubate. How are we going to get evidence that patients benefit from intubation?
Actually, there is evidence that medics can intubate. With aggressive medical oversight, high success rates and near zero esophageal intubation rates are not only possible, but should be expected.
This is from one system with aggressive medical oversight.
Our paramedics successfully intubated 95.5% of all the patients receiving succinylcholine. This is comparable to other published success rates for prehospital, paralytic-assisted intubation 4-7 (Table 5).
We had a total of six unrecognized esophageal intubations. This rate of 0.4% is similar to the rate of esophageal intubations in other studies of paralyzed patients. 2,7
In 1990, we added capnography and a tube aspiration device to all paramedic units. Since 1990, we have had only one case of unrecognized esophageal intubation, a case in which an end-tidal CO 2 value of zero was ignored. It is likely that the addition of capnography and a tube aspiration device has, and will, decrease the incidence of unrecognized esophageal intubation. 
We feel one critical aspect of our program that has contributed to our success is the combination of excellent training and skill maintenance coupled with strong on-line and off-line medical control. Without this combination, the use of prehospital succinylcholine should not be undertaken.
In our study, prehospital succinylcholine appears to be safe and effective. The next step is a controlled, prospective study utilizing a large single system or multisystem approach. This should include outcome studies to determine not only whether the paralytic agent is safe and effective, but also whether its use affects outcome. 
Using systems like this, we need to study the outcomes to see if the effect of intubation is positive. Unfortunately, the outcomes research has generally been in systems that do not seem to have high quality quality. What is the point of studying the outcome of bad airway management? We already know it is bad. What we wonder about is - Why is bad airway management tolerated by those responsible for oversight of airway management?
It appears to be clear that medics can intubate at a rate that would be acceptable in the hospital. We need to stop making excuses for the systems that do not maintain this level of competence.
Still, we need to evaluate the effect of intubation on outcomes.
Not the effect of intubation by National Registry Parrot Medics, but the rate of intubation by competent medics.
If we refuse to evaluate outcomes, we should not be intubating.