Let me share some insight, at least from Europe. I've done interviews in Greece (where I'm from), Belgium, The Netherlands, Luxembourg and most recently UK.Just to be clear, I've not interviewed in all countries for developer roles as I've been doing Dev management and architect roles for the last decade.
I've only once had a code test, which I did from home with a time restriction. Then they checked and used some parts of it as discussion points. I got actually hired there. The test was ok and yes didn't reflect the job but showed if the candidate had some degree of attention to detail and the ability to google. Later on, they did the same interview to a former colleague of mine who failed on the subtleties and got rejected although this person is one of this commando people that will carry you out of shit situations. Recently, I was asked to prepare a presentation.
If you ask me, code tests could have some merit if you find something simple and you don't take it too seriously. Just use it as discussion points. Most important aspect is the discussion but to be able to proper evaluate candidates you need to be relevant and this is where the problem lies.
I actually think that biggest mistake done is this perception of hiring the best fit for an spot. Like it or not, most jobs don't differ from each other. A CMS is a CMS and yes we've all re-invented the wheel but only in our dreams is our code and product so unique. Hire someone who fits the profile, has potential and give it a try instead of spending so much time trying to find the best person. At least in Belgium this is the biggest mistake. To borrow an expression, they are kind of looking someone to be wedded with the job and this is wrong. If the talent is good then he/she might stay only if properly incentified. So I say, get people to get started, don't waste time and if doesn't work try again but don't wait to find the person while everyone else has moved on.
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