The "if" is doing a lot of work in that sentence!
Electronic hardware is extremely reliable. The odds are that your hardware won't fail in the first 3 years - and if it does that's most likely to happen in the first few months when it's covered by the standard warranty. Esp. when you factor in the usual exceptions like "wear and tear" or "mishandling".
Bathtub curve - Wikipedia
Extended warranties are a nice little earner for companies that sell them because they cover hardware during the period when they are least likely to fail. The average customer is going to lose money - the company sure as heck isn't going to risk losing out. General rule is "never insure that which you can afford to replace/repair".
Maybe it seems to be worth it for "peace of mind" if you focus on a single purchase... but if you add up the cost of extended warranties across all of your gadgets and appliances over time, they are a waste of money unless you are very unlucky.
Warranties with accidental damage/loss/theft coverage are a bit better (esp. for people who can't seem to avoid dropping their iPhones) - but even then you'd probably get a better deal by adding the item to your home insurance.
