Post
The humbling art of watching real humans completely fail to understand the thing you thought was obvious.
Playtesting is the process of having people play your game while you observe, take notes, and resist the overwhelming urge to tell them what to do. It's the single most important activity in game development, yet many teams skip it or do it too late. The golden rules: you are not your target audience, what players say they want is not what they actually want, and if a playtester gets stuck it's your fault, not theirs. Every game that feels polished went through dozens of playtest iterations where beloved features were cut and assumptions were destroyed.
Example
Valve's playtesting culture is legendary. During Portal's development, they watched playtesters through one-way glass and discovered that people didn't look up -- so they redesigned puzzles to teach vertical thinking gradually. Supergiant playtests Hades builds weekly at local events, iterating on weapon balance and encounter design based on watching hundreds of real players.
Why it matters
You cannot design a great game in isolation. Your brain fills in gaps, forgives jank, and understands systems that are genuinely opaque to newcomers. Playtesting is the reality check that separates polished experiences from developer fever dreams. Skip it, and you're guessing. Do it, and you're designing with evidence.
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