This isn't true. The worst developers I know are also the most confident. They think their code is perfect the first time and they don't need to learn any more because they believe they already know everything there is to know. The more confident they are the worse their quality of work is. Luckily they are few and far between.

I'm not saying nobody should have any confidence only that having too much is very detrimental.

> Anybody who is hiring (i.e. everybody)

We aren't hiring.

> more than half the time I reckon companies are dissatisfied with the programmers they hire

Your organization has a problem. We've hired "duds" only a few times. The vast majority of the programmers we have hired have been just fine. Or maybe your expectations are just entirely unrealistic?

>So there is actually a huge supply of average programmers that nobody wants. The average programmers aim at the "barely works" bar, and having hurdled it think they are senior programmers. A year or two under their belts, they demand their incredible wages.

That has not been my experience.

> Love what you do because it's a crappy, horrible job if you don't

You don't have to love it, just not hate it.