There is a difference between striving for excellence and striving for perfection. The first is attainable, gratifying and healthy whereas the second is often difficult to attain, frustrating, nerve wracking and results in time-wastage and stress.
Ask yourself what would happen if I do not do those activities aimed at perfection at all? If you are brutally honest with yourself, for some the answers may be ‘nothing would happen’. Peter Drucker says, ‘I have yet to see an executive regardless or rank or station who could not consign something like a quarter of the demands on his time to the waste paper basket without anybody noticing their disappearance’.
Learn to decline tactfully but firmly every request that does not contribute to your goal of striving for excellence. If you point out that your motivation is not to get out of work but to save your time to do a better job on the really important things, you will have a good chance of avoiding non-productive tasks.