Lindy's Law
The future life expectancy of some non-perishable things, like a technology or an idea, is proportional to their current age.
Named after Lindy’s delicatessen in New York City, where comedians gathered to discuss their craft, this effect holds that the longer a non-perishable thing has survived, the longer it is likely to continue surviving. In software, it is a useful argument for choosing older, battle-tested technologies over newer, less proven ones: a technology that has endured for decades is more likely to still be around in the coming years than one that just appeared on the scene.