To add that Amorin did not make Sporting strong overnight, it was not in the first season that he arrived that he made Sporting strong, in the first season he began to organize the Sporting squad well, he stayed for 4 seasons as Sporting's coach, this allowed him to create a good team and that is what Manchester United needs, they need a long-term coach, someone who organizes the team and stays with the team for many years, something like 8 or 10 years.
True, but you forgot how Amorim transformed Sporting in matter of months. It's totally different when you're seeing how he's performing at United. Harder league, more quality coaches compete, and high intensity. It's all makes him struggle, and now his club at the mid - bottom table.