I stayed 100 nights with Starwood in 2016 and was assigned an Ambassador for 2017. My Ambassador was excellent.
However members certainly have had varied experiences. Different Ambassadors provide different levels of service. Each person has different skills. The program itself provides guidelines but some go above and beyond. And workload matters. Now that the program is scaling to support top elites at Marriott too, Marriott’s metrics are being put into place.