A quick anecdote to illustrate: When Apple first started to livestream events, I talked with a high-level Apple exec who worked behind the scenes to coordinate its efforts. 

They explained to me that the amount of traffic Apple saw during that event actually disrupted internet services on the west coast, especially the Bay Area. Completely saturated it.

Things have changed, but even now, infrastructure companies like telecoms can't always deliver service at peak times.

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