The conscientious person sets themselves standards of excellence that are humanly possible to reach. They know how to balance out their efforts and determine their priorities without neglecting the importance of details. They remain flexible and know how to adjust their own expectations according to the context or the importance of the task. They are their own critique; they own their mistakes and try to fix them. They find joy and satisfaction in completing projects and reaching personal goals. They perceive the future in a realistic fashion, et try to prevent any difficulties. If difficulties come up, they try and find solutions to use.
The perfectionist person sets themselves standards of excellence that are extremely difficult to reach, even impossible. They don’t know how to balance out their efforts, sometimes overinvesting themselves in tasks of lesser importance at the expense of some of higher priority. For them, details are as important as the bigger picture, and they remain inflexible in their choice of priorities and their way of working. The perfectionist encounters difficulties working as a team or delegating. They constantly second-guess themselves, and don’t acknowledge their limits and imperfections. Their value as a person depends on their success and achievement. They severely judge themselves, and don’t take criticisms well. The tiniest mistake is experienced as a crushing defeat.  The perfectionist is perpetually unsatisfied and very often experiences anxiety, shame and guilt. They fear the future and dread failure.
Source: Louise Careau, psychologist (Laval University)