Amazon Prime is particularly heinous about using dark patterns to confound users into risking forgetting but ultimately you’ve already paid for the month, year
I can confirm this to also be the case with most streaming giants plus the less-giant Shutter
Edit: comments have pointed out some notable exceptions such as services through Apple and HP Instant Ink
All subscriptions through Apple do this.
The upside is if you cancel a yearly subscription after just one day you get basically all your money back.
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