Improve the function of a system by removing unnecessary features.
System B is roughly 6 times as complicated as system A because of interactions between the features.
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Features interact with each other which exponentially increases complexity.
Every extra unnecessary option one uses in a solution has a multiplier impact in complexity. Sometimes I refer this as factorial complexity. Factorial numbers are like 5! which means 5 * 4 * 3 * 2 *1 = 120.