The same problem exists from the recruitment side. Most recruiters play it as a numbers game. The more candidates they send to a company, the higher chance of collecting a fee. My experience with external recruiters is for the most part disappointing. I believe the biggest issue is that recruiters don't fully understand the role they are sending their candidates to. It’s common to see candidates with little experience in a technology, but because they dabbled in it at some point, they are still forward as a valid prospective. More experienced candidates are able to recognise these mismatches and avoid wasting their time on unsuitable interviews, but less experienced engineers won’t. While hiring iOS engineers, the mismatch is not as big. Doing iOS in one company is likely to be the same in another. The language is the same, tooling as well. The likelihood of a different architecture exists, but it won’t take long for one to get used to it. This problem is particularly pronounced for backend roles, where the specific technologies and expertise required can vary greatly from one company to another. The expertise in scaling something like a chat app, is quite different from processing vast amounts of data. There are just too many possibilities. While in iOS, it’s usually the same run-of-the-mill: make requests, parse json, display something. Because backend work can be dramatically different, even if you are using the same language, there’s a high chance of getting a candidate that won’t fit. And that’s what I have seen with external recruiters approaching me for a backend role we are currently hiring. At a glance, you can see that we need someone with experience in Python. And that’s what we get: people that at some point have done Python. But we are also looking for someone with experience on data-intensive systems that can scale to millions of connections. This last requirement is mostly overlooked. And of course, anyone can become an expert in something they never worked on. It's is not the ability to learn that is the main factor, but rather bringing that already existing experience from elsewhere.