We're all familiar with poorly written translations and incomprehensible user guides. They are good for a laugh, but don't you want to use your translations to market your products successfully?
Technical documentation and any other texts you publish are advertisements for your company. These texts should therefore not only read well but also achieve their purpose. Your customers can only use your product correctly if they understand your manual or online help, regardless of whether or not the text is a translation.
This means a translation must read as well as the original. This is possible only if your translator is technically competent and linguistically skilled. Do you want your translations to be done by a qualified professional?
And the result will be as professional as your own product.