I've recently been reading Maverick by Ricardo Semler. It's an excellent read so far and chronicles the transition of Semco, a Brazilian manufacturing company, from a traditional corporate structure to one of the most unusual and innovative companies in the world. Part of that transition was due to Semler learning to overcome his own 'time-sickness' which was causing him very high-stress and induced physical symptoms such as a constant sore throat, migraines, gastritis, fainting spells, etc…. The following are the causes of this sickness he identifies:

Cause 1: The belief that effort and result are directly proportional.
Cause 2: The gospel that the quantity of work is more important than the quality of work.
Cause 3: "Things are a little uncertain at the office right now. I'll just have to work a little longer until they straighten out."
Cause 4: Fear of delegation, and its cousin, fear of replaceability.