[kbenson]

I would say programmers are like skilled laborers in this simile. Some are plumbers, some are electricians, some are woodworkers, some are handymen. I wouldn't hire a plumber to wire a house, nor an electrician to plumb it. Either might be able to do the job, or might not. A handyman probably can, but most likely not with the same quality, or knowledge about how to fix more specific or harder problems.

I don't expect a programmer that's been steeped in the world of UNIX daemons to write a good customer facing website on their first attempt, and I wouldn't expect a front-end Javascript programmer to know how to deal with multiprocess programming in C/C++. Asking them to do so may not result in something "with no problem". At least not in an acceptable time frame.