Perfect tool - imperfect idea

Whatever the designer's skill and preference for any particular ideation tool, the ubiquitous pen and paper sketch may seem the perfect tool for expressing and capturing ideas; its immediacy and ease of use. Yet whatever ideation tool is employed, and to whatever level of perfection, the idea itself, in its substance, cannot be perfect. This is because the word, or concept of, perfection suggests "a finishing" or "bringing to an end", whereas the idea, in a creative context, remain incomplete or open-ended implying comparison to other ideas. Better then, perhaps, to talk about "excellent" rather than "perfect" ideas, where the former imply comparison. However, the idea expressed may be considered perfect when it perfectly serves its purpose.