The biggest shock to most industry candidates is the sheer size of the test discipline at Microsoft and the amount of clout they wield. The developer to tester ratio at Microsoft is about 1 to 1. Typical for industry is about 5 developers to 1 tester and sometimes 10 to 1 and higher.
When you are outnumbered like that, a test organization is usually focused on survival rather than evolving their engineering skills and practices.
Source: How We Test at Microsoft, MicrosoftPress (Page, Johnston, Rollison)