I think if you talk to a lot of developers they would like to be at a "level 4" as you call it but the pressures and deadlines on them don't allow for that as o

I think if you talk to a lot of developers they would like to be at a "level 4" as you call it but the pressures and deadlines on them don't allow for that as often as they'd like. Of course it's in the best long-term interest, but management are not doing this type of long term thinking. I think it's easy to judge from academia where you do an assignment, then move on to the next. But it only takes a couple of years in a real-world environment for code to get incredibly f'd up even if the developers were trying to be diligent. People come and go, platforms go out of style, programming fads come and go and, of course, one or two mediocre people on the team add their code to the mix.