I wonder too, and I do not know.

From some developers I've worked with in the past, they ask their colleagues a lot, try cut & paste until it works and ask detailed questions on StackOverflow or similar sites.

The bigger the team the longer they can stay with the company until they are made to leave. In some very large companies I've worked with, with large teams, they stay forever even when colleagues are unhappy with their performance. In those companies it is often more important to have all positions closed than have (good) developers in every position.

When looking at CVs - not scientifically - some stay only some months with a company or stayed for a long time with a large enterprise.

At a previous role many years ago, I was part of the hiring process for someone to replace me. (moving to a new job soon) I had 3 years of Java experience, and 4 years of coding experience in general. So pretty junior role. And we thought it would be easy to get someone.

This one guy we interviewed had 15 years of C# experience. I thought great, he might not know Java, but he can pick it up quickly with that much experience. I was a little concerned that someone this senior was applying for such a junior role, but so far he was much better than any of the other candidates.

Just as a sanity check, I asked him to write something similar to fizzbuzz. It was actually even easier. He couldn't do it. And I thought that maybe he thought I expected him to do it in Java, so I said he can do it in C#, pseudo code or any language he likes.

He couldn't even write a single line of code. I ended the interview right there.

I don't know how deluded this guy was. Or if his CV was made up. Or if he just conned his way into his previous roles. There are countless people like this. It is surprising what you'll find out there.

> How can someone possibly call themselves a programmer… when they can't even pseudo something like fizzbuzz?

Agreed. On the other hand, I can count the number of times I've used modulo professionally on one hand, so I wouldn't be too shocked to encounter a competent programmer who had't heard of it.