I think i've only used up maybe 3 lipsticks in 45+ years, but that's 'cuz: i like to switch colors, i have waaaay too many, and i don't even wear lipstick every day.
Experts say toss 'em after 1 to 4 years, depending on the expert... I understand that keeping them in the fridge helps them last longer, too, although i don't do this myself. I stop wearing mine when they smell rancid.
I've had little-used lipsticks that were still good after 10 years. It helps that i live somewhere without temperature extremes -- East Bay of San Francisco Bay Area (Berkeley/Oakland), where most of the year it's between 55 and 68 F. (circa 37 to 50 C.), although we have a few days in the low 40s (January) and a few in the mid 80s (September). And i don't turn the heat up much in the winter, so that helps, too. Also, i don't share mine, so i'm not collecting extra viruses, bacteria, and fungi from friends.
I'm sad because the MAC lipsticks i bought in the mid-1990s -- Lust (frosted pale blue violet), Grid (frosted dark blue violet), and Cyber -- finally went "off" toward the end of 2012.