"One study...about retraining Windows users on Linux concluded that 80% of the people who switched to Linux needed only about one week to retrain themselves to use Linux properly for their needed job. That does raise the question about how long the remaining 20% took to adjust, and even if it wasn’t a significantly greater length of time, it does indicate that retraining isn’t going to be a one-size-fits-all job... In the end, though, the only truly accurate and useful TCO study for comparing Windows to Linux is the one you conduct yourself. You can look to other TCO studies to get an idea of how to model one for your own organization and needs, but you’ll need to know your own environment intimately to get a real grasp of the cost. "

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