If that's the case, most companies would just give that person the work to do. If they've already got the time and experience, very few managers [in the real wo

If that's the case, most companies would just give that person the work to do. If they've already got the time and experience, very few managers [in the real world, at least from my experienced] have the foresight to use that person to train another developer. Usually they'd just give that person the work until there's so much work they can't scale and then someone else would be hired to pick up the shortfall... Of course, the first developer is still so snowed under that they have little to no time to mentor the new guy. So they look for someone who may be experienced in the language but only a mediocre developer by definition. In real world terms, it appears to be expected that a senior developer can just be dumped into the empty seat and get on with it - thus, the expectation also appears to be that this senior developer needs to understand the language and pick up the business knowledge quickly enough to be productive without costing more than absolutely necessary.