Unfortunately in the business world today, too many use anything to increase sales... a tire's condition is a function of care and exposure... rubbers do not last forever like plastics so there is a life expectancy but that range is wide and variable... even when someone says their motorcycle was always garaged, but they rode it to work everyday- then the bike sat outside in the sun all day long everyday... with dates placed on everything (in the US), then marketing folks tie campaigns to them to increase sales... I know too many people that don't think for themselves and look at these dates and just take them for science. That is wrong. Milk will go bad before it's date if left out to warm up, it will also last long past it's date if kept cold more, longer, or if left unopened longer... This is a good analogy for tires... They are not made to order or upon ordering but mass-produced at numbers justified by sales projections. Then they are shipped, stored in warehouses, distribution centers, etc... You can examine tires and ascertain their condition with knowledge of how they were cared for... that is a key part, without that knowledge, lean more toward the norm... The pencil erasure analogy is good but you also need to realize that small items dry quicker and hold less moisture. It is also a different compound. It will illustrate what happens in theory but not exactly... Use the same eraser and it last longer if used versus if left to sit... I grew up in a time when nothing had a date, you had to use your head...
