I find the autoplay so annoying because it hides the thumbnail which was carefully designed to communicate why I should click on the video and replaces it with, usually, a talking head or stock footage. Often the video gets inexplicably added to my watch history, and if I do choose to click on it I have to go back to the beginning because I missed the start of the audio
This has been one of the most frustrating things I run into with Youtube scrolling the page. Can’t leave your cursor on the page while scrolling without managing to have the spacing shift the thumbnails just so slightly so that your cursor lands back into a thumbnail for an autoplay to start and add to the metrics.
As to the reason, at least with Youtube and Facebook, the answer is obvious: they want to increase their ad revenue by claiming additional “plays” or “interactions” or whatever they want to call it today. I remember realizing several times over the years that I had been conned when I paid for ads. The top-level numbers looked good, but when I dug in, I realized they were all faked.
Same stuff with the mobile youtube app. If you so much as graze the screen anywhere while watching a video the replay speed doubles. This is so sensitive that even a tiny unintentional finger touch, or a water droplet landing on the screen triggers it. Whoever thought that is a good idea as a feature, i can’t comprehend.
Plus they have no data to see how badly their feature annoys me. From a metrics perspective “the user wanted to fast forward for 5s” looks the same as “a careless finger cradling the phone triggered the fast forward and it took the user 5s to realise what is going on and adjust their hold, now they are annoyed at how fragile this app is”. Someone might have even used the statistics of all the inadvertent activations in their promo package to show what a popular feature they made!
I mean, I suppose you're right. However, that being said, a case is a good idea nonetheless, just as is a screen protector. A good case protects the phone against damage from dropping, just as a good screen protector does the same for the screen.