Creative jobs are different from managerial jobs. I started noticing the difference when transitioning from being a management consultant to a presentation designer. It especially obvious with being sick. As a consultant, I could usually function pretty much normal with the help of some coffee until drastic body feedback such as fever or a splitting headache prevented you from going any further.

With design work it is different. You notice that something is "not right" in your head 1-2 days before the onset of other symptoms. You can't come up with any good ideas, or you can't focus on your creative work and decide to do the monthly accounting. So, sometimes after these 1-2 days, I do actually develop symptoms, or things disappear while others in close proximity do get sick. 

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