Why is validation a requirement for the manufacture of medicinal products

hey im totally new to validation and im currently doing a paper on why validation is a requirement for the manufacture of medicinal products( 4000 words). im currently at a loss as to know what they are looking for. layout content etc. if anyone has done one before or could be of any assistance any help asap would be greatly appreciated.
cheers

Validation is very much important in the process industry especially for the medicinal products. Because through validation we know the authenticity and robustness of any process or method.

Yes. I agree with you. Validation not only says the robustness and performance of the machine but also the life of the machine. It is followed very strictly in medicinal products because a small fault in machine may cause a big hazard.