Short answer: "non-OEM" by itself isn't the risk. The real line is whether the pad is a certified, traceable product from a company that will stand behind it—versus a no-name pad with no testing documentation, no marking, and no way to trace a failure back to anyone.
The rules aren't the same everywhere. In Europe, replacement brake pads sold legally must carry ECE R90 approval (mandatory for pads since 1999, extended to discs for newer models around 2016). R90 requires the pad to demonstrate performance within a set tolerance of the original part across cold performance, fade, compressibility, shear strength, and hardness testing, and the pad is marked with an "E" number identifying the approving country.
In North America there's no equivalent federal rule requiring aftermarket brake parts to prove they match OE performance—FMVSS covers new vehicles, not the aftermarket pad you buy at year five. So in the US, certification is largely voluntary and brand reputation does the work the regulation does in Europe.
What cheap pads actually fail at is rarely "no brakes at all on the first stop." It is usually fade when hot (repeated hard stops, mountain descents, towing), inconsistent or weak cold and wet bite, noise and vibration, faster rotor wear because the friction material is too aggressive or badly formulated, and—the genuinely scary one—friction material separating from the steel backing plate, or a backing plate too thin to hold shape under load. Those are quality-control failures, and they tend to cluster in the unbranded, un-audited end of the market rather than in the budget tier of an established friction manufacturer.
Where the line falls: a smart deal is a budget-priced pad from a known friction brand with R90 marking (if in Europe) or documented testing and a real warranty (in the US). For normal commuting, a decent budget pad will stop your car fine. Independent comparative testing generally finds the gap between good OE-replacement pads is small in everyday driving and widens under repeated hard use—that is the honest version of "OEM is better."
A dumb shortcut is unbranded marketplace generics, counterfeits of well-known brands (a real problem with brake pads), anything claiming "racing" performance with no data, or a set that doesn't include proper shims and hardware.
Also factor in that cheaper pads sometimes cost more over their life if they wear quickly or chew through rotors, and that installation and rotor condition matter as much as the pad. If you tow, drive loaded, or regularly descend long grades, buy up—heat capacity matters more than price.
One caveat: I can't verify claims about any specific brand, so check for the R90 marking or the manufacturer's published test data on the exact part number before you buy.
