You could notice that often IT job ads contain phrases like
"X years of experience is required." Actually, requiring experience is a useful idea, but after two-three years of experience situation does not differ so crucially - the difference between a candidate with two years of experience and with six years is not so much as can be supposed. The real difference comes from the personal intellect, pro-activity etc. Our memory is not ideal and recall things that we dealt with three-four years ago is not so easy.

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