For us in Poland we have normal high schools, technikum - which is similar, but year longer and you are trained in a job, and zawodówka - which is vocational.
And issue with them is not the school itself, but the type of teenagers that attend them. As much as it pains me, for zawodówka schools - you will get the most demotivated people. And even if you really just want to be trained, you will get into an environment that will destroy you.
I wonder how Germans are faring with this.