"Rather than survey a bunch of users on every decision, the Mac team decided each issue among themselves, invariably going for the option that might amuse a user the most, that would give a user the most pleasure, and therefore imbue the Mac with personality."

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Why Apple is great at interfaces when others are not | TechRadar Team | TechRadar UK (via soxiam)

I would also argue this leads to bad decisions, e.g. iTunes zoom (maximize) button activates the mini player.