If the traces aren't thick enough, or too many high
power LEDs are served
power by too thin a trace, or they're shedding too many watts as heat for the trace's dissipation ability, or they're not well located on the solder pads, or the solder isn't good, or the backing material is of lesser quality, or if the traces adhere poorly to the backing material, or if there's no conformal coating, etc. Also some strips will use lower quality LEDs that don't provide good color rendition, making it harder or impossible to see certain colors, hues and tints. And some LED strips have smalls ICs on them, and if they're of poor quality, they might emit EMF
noise.
All things that could lead to shorts,
overheating, fires,
radio noise, or early end of life for the strip. Or just make it harder to see.
My main concern was fire, it's easy to pack a ton of LEDs on a strip that is unable to keep the LEDs cool in some circumstances. This could create hot spots that could lead to a fire, over time.