"40% off" only means something if you know what it's 40% off of. A lot of online "sale" pricing is measured against a list price that the item never actually sold at — which makes the discount close to meaningless. The fix is simple: look at the price history, not the sticker.
What actually matters
- The recent average, not the all-time high. A game that briefly spiked to $80 and now shows "50% off!!" at $60 isn't actually a deal if it's normally sold for $55. Compare against the last 60-90 days of normal selling price, not against whatever the highest number ever charted was.
- How long the price has held. A price that's been stable for two months and just dropped is a more meaningful signal than a price that bounces up and down weekly — volatile listings are noisy and the "discount" might reverse in a day.
- Who's selling it. A price drop on the listing fulfilled and sold by Amazon itself behaves differently than a third-party seller's price, which can include shipping games or used/open-box conditions mixed into the same listing page.
A quick gut check
If a deal looks too good, check two things before buying: the seller (is it Amazon or a third party you don't recognize?) and the condition (new, used, or "open box"?). Both are usually visible right on the product page, just not always above the fold.
This is exactly what the filtering on this site is built to do automatically — see How We Pick Deals — but it's worth knowing how to check it yourself for anything you find elsewhere, too.