Andras is said to sow discord, and to kill the operator and his companions if the operator is not careful. It is the most explicit threat in the catalogue, and it belongs to a small group of similar notes scattered through the seventy-two.
Elsewhere the warnings are milder and procedural: a spirit is proud and must be addressed bare-headed; a spirit's breath is foul and the operator should hold a silver ring to his face; a spirit must be received courageously; a spirit will not answer truly unless it receives offerings. Together they form a thin layer of caution over an otherwise businesslike list.
Their function is best understood as generic rather than instructional. Warnings of this kind are a standing feature of magical literature across periods and languages: they establish that the material is potent, that the practitioner is undertaking something serious, and that failure will be the practitioner's fault rather than the text's. A book that promised results with no conditions attached would be refuted by its first disappointed reader. A book with conditions is not.
There is a second function, specific to this corpus. The Goetia's frame is Solomon's mastery of the spirits, which requires the spirits to be dangerous enough that mastering them means something. A catalogue of entirely compliant servants would undercut the premise. The occasional lethal entry keeps the frame standing.
None of which requires a judgement about the tradition. It is simply how texts of this genre are built, and Andras's clause is doing work that the same clause does in a herbal, an alchemical recipe or a book of surgery from the same century.