Hiring devs to just think is part of what creates these convoluted mess of systems. It's impossible to convey and idea well enough that another person could implement it in the same fashion. Look at language specifications: they are written by top-tier developers, but when implemented by other equally top-tier developers, there is an inevitable difference of opinion.

Senior developers should be writing code for important systems, and juniors should be writing the less important bits. That way, they get the opportunity to experiment without the company being stuck with a critical system written by a person who reinvented Yet Another Elliptical Wheel.

Mentoring is important and all, but at some point, you just have to start working.