In Germany to persuade is to inform persuasively. Persuasive argumentation guides an audience to its logical conclusion. Selling the conclusion is not necessary.
In the U.S. to persuade is to sell persuasively. Persuasive argumentation leads the audience to a choice. The audience is then asked to make a choice. The presenter asks the so-called closing question. Yes or No? And the American audience expects it.
Americans sell. They are salesmen. There is little substance. They don't persuade. Americans put on a show. The audience has to either buy or reject. Germans feel very uncomforable with such a frontal approach.
Germans inform only. They give academic lectures. Germans don't sell. The audience is left hanging. Perhaps they are afraid to ask the closing question. Americans don't buy if you don't ask them to. "We're ready to buy. Why doesn't he ask us?"
Advice to Germans
Overcome your inhibition to recommend a clear choice (your choice) among the options. Ask the closing question. Ask for the order. The worst that can happen is you'll get a no. So what? Life will go on.
Advice to Americans
Do not confront your German audience with the closing question. Americans can easily come across as pushy used-cars salesmen. Take almost a take it or leave it attitude. Germans know that you want them to say yes, to buy.