The key perfectionist symptom is that you define success narrowly and unrealistically, and failure broadly, and then punish yourself harshly, via an abusive internal dialogue, for perceived failures. You may be familiar with that internal dialogue; it goes something like this:"What's wrong with me? This work is easy. Anyone can do it. Why am I so lazy? Why am I so uncommitted? I'm never going to succeed. I'm just a loser. And I've had all these advantages. I'm just a fraud." Etc.
Note that perfectionism is not the same as having "high standards" - high standards are fine. Perfectionism is all about having unreasonable or unachievable standards, and harsh self-punishment.
Grandiosity is a huge part of perfectionism. It's the deluded idea that things that are difficult for other people should be easy for you. Grandiose people think, for instance, that they should be able to write a thesis without having to give up any professional or personal commitments. They always have a rationale. "I'm well organized." "I know my subject so well." "I went to a top school." Etc. But the data points don't connect: it's still delusional grandiosity.
Another perfectionist symptom is overidentification with the work. If a work session goes well, perfectionists feel like king or queen of the world; and if it fails, they feel like the worst loser in the world. This only increases their terror of failure, of course.
Other perfectionist symptoms include:
Focus on Product over Process - "I don't care what else is going on in my life, or with my work: I'm just going to sit here and write my ten pages, dammit!"
Focus on External Rewards over Internal Ones - "If my book doesn't sell a million copies, I'm a huge failure." (That's unrealistic goals and overidentification, too, in case you didn't catch it.)
Deprecation of the True Processes of Creativity and Career-Building. - "My book is so timely it's bound to be a best seller!" (It takes a lot more to create a best-seller than just timeliness.)
Labeling - "Why am I so lazy? "Why am I such a wimp?”
Hyperbole - "This is the worst paper ever.”
Dichotomization, or seeing things in black and white no shades of gray. "If I don't get an A, I'm a total failure."
Shortsightedness. - Overfocusing on the current project, moment, or work session. "Now or never," "Do or die," "This project will make or break my career." Etc.
Competitiveness / Comparisons. - "Joe is able to do sports, work twenty hours a week, and take 16 credits, so I should be able to, too!" But perfectionist comparisons are inevitably flawed, because the comparison is not designed to elicit insight but to coerce the perfectionist into working. In this example, for instance, the perfectionist person conveniently forgets that Joe has an easier major, and that his job allows time for study.
As you can see, perfectionism is a real cornucopia of antiproductive habits, attitudes and ideas. We get it from society - especially the media, which uses perfectionism to sell products - and from our parents and teachers. And it's almost always catalyzed by toxic rejections, especially from teachers, publishing professionals, or other authority figures.
Perfectionism tends to afflict the best people: the ones who care the most, hold themselves to the highest standard, and seek to do the most good. Fortunately it's solvable. Get a summary of how to solve it here, or buy The 7 Secrets of the Prolific here and get the whole story (and instant ebook access).