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Sometimes I have clients that from start gives you huge flow of words about "how task should be done in details", like "you must use SQL Server here", "should do this in do-while-loop", "should make two functions like that, and they should run in parallel", etc..
But they never-ever give you any word about "what is this task about?" and "why it's needed?". Even if you ask them about this questions directly, they only can say "I don't know, but this work should be done".
Doing this jobs is realty hard and despairing, because you don't understand project as part of some system - there is no system yet, and maybe never be.
Is there any way that can help deal with this kind of clients?