I've got shorts that are 10 years old that are still fine, but that's a rarity. These particular ones were Performance Ultra from way back when and have seen a lot of use but still fit, have good chamois, and since they have sewn leg bands, haven't had issues with elastic breakdown as I've had in some other shorts. I've thrown out a lot of shorts in the time that these have lasted. Also have a couple pair of Shebeests that are 4-5 years old and still going strong.
Emily
2011 Jamis Dakar XC "Toto" - Selle Italia Ldy Gel Flow
2007 Trek Pilot 5.0 WSD "Gloria" - Selle Italia Diva Gel Flow
2004 Bike Friday Petite Pocket Crusoe - Selle Italia Diva Gel Flow