Purchase protection insures your purchased items from the date of purchase in the event of physical damage or theft. Details & cards that offer this perk.
Paying for a purchase using a credit card that offers purchase protection insures that purchase for a set amount of months in the event of accidental physical damage or if it's stolen. This is a really big benefit that can provide you some comfort during the first few months of your purchase. There's nothing like buying something only for it to break or malfunction within the first few months. With purchase protection, you'll be covered.
The length of purchase protection will depend on the card provider. Most cards offer 90 days, but there are some that offer as many as 120 days and as little as 60 days. The amount you're insured for also depending on the card. You'll want to check what your card offers and what they consider to be non-eligible items.
For me, purchase protection is more important than earning rewards if I have to decide between the two. There's been a few times in which purchase protection has saved me a couple hundred dollars and that's worth more than any points, miles, or cash back I could earn from any card. While it is solely up to you, I highly recommend putting big ticket items on cards that offer purchase protection as you never know what might happen.