Hasty decisions of any kind are anathema to Germans. A German manager is expected to work through the mediation process carefully. Adequate time is taken to gain a clear overview of the dispute.
An optimal resolution which demands time is better than a suboptimal resolution arrived at quickly.
Moving quickly is critical to success in the U.S. Americans become impatient if too much time is required to resolve a conflict. Festering conflicts are disruptive for any team.
A suboptimal, but prompt resolution, is often better than an optimal, but late one.
Quick (hasty) decisions are rarely good decisions. If poorly resolved, a conflict resurfaces, demanding a repeat of the resolution process. Americans all too often address the symptoms, not the illness.
The negative effect of a festering internal conflict on a teams internal cohesion, and thus performance, is almost always costlier than the benefits of a perfect resolution. Maintaining forward movement has priority.
Advice to Germans
If you lead an American team, move much faster than you normally would. The longer the conflict festers, the sooner your American team will question your leadership capability. If you need time, nonetheless, explain to the team why. Don‘t leave them in the dark.
If you have an American boss be prepared for a decision you might like or not like, but either way the decision will come much sooner than you think.
Advice to Americans
If you lead Germans, and a conflict has been escalated up to you, do thorough due diligence. That takes time. Don't rush it. In the German context Aktionismus (actionism) - acting before thinking or "shooting first, then asking questions" - is a criticism which goes to the heart of your reputation.
If the issue has finally caught the attention of your German manager, alter your internal clock. The wheels of justice in Germany move slowly. Remember, a German working in the U.S. - colleague or boss - is national-culturally still German. Like snails or turtles, we drag our "homes" with us wherever we go.