I have interviewed hundreds of candidates and worked for many projects over past 20 years.

> Are these candidates truly incapable of doing the job, or are the understanding of what the job entails misunderstood by everyone involved?

Yes. There is a lot of candidates who utterly incapable of doing their job.

Let me share a story.

I remember one day I wanted to pass driver's licence exam here in Warsaw, Poland. Poland is known for having one of the most difficult exams in the world.

There was a group of people standing there that seemed to be already knowing each other. One new person came, greeted them and said they just blew the exam. So they ask him "Where did the guy fail you?". It is difficult to translate, but the assumption in the question was that it was the examiner's decision rather than examinee's fault. Then I learned that he made some stupid mistake and that this is 25th attempt at the exam. Then they started discussion about how unfair entire process is and how impossible it is to pass it.

I went and passed on the first try because I have honestly prepared.

It is the same with software development. A lot of people just keep complaining and complaining about unfairness of it while they are doing absolutely nothing to get better and effectively have the same level of competence as the people in the story. And all the while they also earn a comparatively very good salary (at least here in Poland if you are software developer for a foreign company you are already getting more than average salary that most non-developers need many years to achieve).

My every other interview is a person that cannot answer any of the questions I give and then, can't write a simple piece of code I ask them to.

It is possible that a small percentage of these people are truly stressed and I try to employ stress relief tactics to help this on an interview.

But I honestly believe most of these people simply can't program.

What is even more interesting is that these people come mainly for senior development jobs (I don't interview junior developers) and that they come through agencies that supposedly screen them and some even hire them and bring them forward as contractors.

> Sounds like an extreme outlier. Even companies like Google who are notorious for having long drawn out interview processes mostly just have long wait times in between rounds and recruiter calls. They don't involve 24 hours of talking to Googlers.

I summed up the actual length of zoom meetings I had and it added to more than 24 hours. Yes, I am an outlier. But it still does not change the fact that I was looking to change jobs and was willing to go through a lengthy process (actually it was fun talking to intelligent people and I wouldn't mind even if I did not get the job).

For me, personally, I am happy to have more time to convince the interviewers that I am the right guy for the job and my good first impression is not just a fluke. The more time I spend on the discussion the better starting point for negotiation I have.

I assume that if they spent a lot of time talking to me and are very happy with my answers they would be willing to pay more than if I was just random person off the street that just lucked out giving couple good answers on a very short interview.