Interview question - when to use stored procs

I've been ask this question in two different interviews...

What is the benefit of using stored proc ? another guy asked... when would you use a stored proc over inline sql

My answer:
Stored proc makes an application database agnostic ... application layer is separate from the data
Stored procs are compiled

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When do we want to use a SP over inline SQL?  I didn't answer this one.

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No matter how much I prepare for an interview... there's always something unexpected thrown at me!