Is it worth buying an extended warranty?
Usually no — for most electronics and appliances the price is high relative to the odds and cost of failure, so skip it unless the item is genuinely fragile or expensive to repair.
beginner
Extended warranties are priced to be profitable for the seller, which means on average buyers pay more than they get back. They make sense only in the narrow cases where repair is both likely and expensive relative to the plan cost.
What it is
Verdict: For most gadgets and appliances, skip the extended warranty. These plans are sold at the checkout precisely because they are high-margin, and the average buyer pays more in premiums than they ever claim back.
It depends on: the price of the item versus the plan; how expensive a repair would be; how failure-prone the product is; whether a manufacturer warranty or your credit card already covers it; and how much financial stress an unexpected repair would cause you.
How to decide: (1) Check what the standard manufacturer warranty already covers and for how long. (2) Check whether your credit card automatically extends it — many do. (3) Compare the plan price to the repair cost; if the plan costs a third or more of the item's price, it rarely pays off. (4) Consider self-insuring — set the plan money aside and use it only if something breaks.
Pitfalls: assuming the plan covers accidental damage (many don't); overlapping cover you already have; and buying peace of mind you could get more cheaply by simply choosing a reliable model.
Worked example
A $400 laptop with a $90 two-year plan: the manufacturer already covers year one, your card may extend to year two, and a typical out-of-warranty repair might be $120. Paying $90 to insure against a maybe-$120 repair that your card might already cover is usually a poor trade.
Failure mode — when it misleads
The most common mistake is buying the plan on impulse at the register without reading what's excluded — accidental damage, wear and tear, and battery degradation are frequently not covered.
How to apply it
Ask: (1) What does the maker's warranty already cover? (2) Does my card extend it? (3) Is the plan more than a third of the item's price? (4) Could I comfortably absorb the repair myself? If yes to that last one, skip the plan.