Your question of why...
Kenone, If I read your question right, it's likely because MS sells versions to a wide variety of customers, that want various levels of control over workstations. From local admin up to Domain manager (with multiple levels of support), there are a huge variety of requirements for IT managers to decide upon. The Wikileaks leaks, for example, could have likely been avoided with proper domain or forced local credentials. With a huge range of variety of customers, come a lot of decisions, and about what is possible. UNIX has had the same notion as Windows for way longer, most users have never had superuser level privs on UNIX boxes. The problem you state is that many software developers, never being forced to write an install for a non admin user, assumed that all installs would be done by admin level privs. It's really not Microsoft's 'fault'. But they created the earlier Windows environment (pre-Win2k) that allowed this behavior to flourish. Hope that helps!
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