Why does this JavaScript loop log 3, 3, 3? (and what it reveals about how JS really works)

Title: Why does this JavaScript loop log 3, 3, 3? (and what it reveals about how JS really works)

URL Source: https://medium.com/@guptabharat297/why-does-this-javascript-loop-log-3-3-3-and-what-it-reveals-about-how-js-really-works-d5eaa7d2922d?source=rss------javascript-5

Published Time: 2026-04-25T21:01:31Z

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# Why does this JavaScript loop log 3, 3, 3? (and what it reveals about how JS really works) | by Bharat Gupta | Apr, 2026 | Medium

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# Why does this JavaScript loop log 3, 3, 3? (and what it reveals about how JS really works)

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_A no-fluff guide to var, let, and const, the basics you think you know, and the weird parts that will bite you in an interview._

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Before I explain anything, what do you think about this code and what it will log?


If you said 0,1,2 — you're wrong. It logs 3,3,3.

Here’s why. And it reveals somethin