Time Dilation - Why an Accelerated Frame of Reference Slows Down Time

Everything is relative.
Or so that's what Einstein postulated over 100 years ago in his theory of special relativity. Just like how another objects observed velocity depends on the velocity of the observer, so too does the observed velocity of light.

As we change frames of reference, the observed velocity of light needs to remain the same and this transition causes what can be considered a dilation of time.

But why does Time dilation happen at all?
Muisc - https://dopeminemusic.bandcamp.com/track/mk-i

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