You can keep lipsticks for up to 2-2.5 years, you know its bad when its dry and not as smooth as when you first bought it.
1-1.5 years, you know its bad when it feels waxy.
8 months to a year, you'll know its bad, the foundation starts smell different.
About a year, this also starts to have a bad smell when it goes bad.
3-4 months, when the mascara dries out.
1-1.5 years, just like the lip liner, it starts to get waxy.
3+ years, when you don't get as much pigmentation as you use to, you'll know when its bad
3+ years, Just like shadows, when you dont get as much pigmentation as you use to, you'll know when its bad