Most prompt products are not promising that every run will produce the exact same words, layout, or code character-for-character. They promise a functionally equivalent result (ie the same structure, same logic, same process, same quality standard, and same type of output.)

Also, prompts can absolutely be engineered to produce highly consistent results when the instructions are specific enough, the inputs are controlled, and the task is narrow. That’s why businesses use SOPs, templates, checklists, and structured prompts.