On average, you can expect the Purple mattress to last between 7-10 years. Purple provides a limited 10-year warranty as well.
This is similar to most other mattress averages, ranking the Purple mattress between a classic foam mattress (100% foam) and a traditional hybrid (foam + coils).

According to the manufacturer, the Purple grid is not expected to break down over time. The hyperelasticity of this material allows it to return to its original shape also immediately, following pressure being applied.
It’s the foam layers below that really limit the expected lifespan of Purple. As with any foam, with regular use, these layers can begin to compress and sag.
A compressing support layer means that the top Purple grid may begin to struggle, as the mattress ages.