In many cases when a government branch or municipality switches away from Microsoft, Microsoft throws money at the government branch or municipality.
For example, When Munich in 2013 migrated to Linux:
"In 2016, Microsoft relocated its German headquarters to Munich. "
"In 2018, journalistic group Investigate Europe released a video documentary via German public television network ARD that claimed that the majority of city workers were satisfied with the operating system, with council members insinuating that the reversal was a personally motivated decision by mayor Dieter Reiter. Reiter denied that he had initiated the reversal in gratitude for Microsoft moving its German headquarters from Unterschleißheim back to Munich."