A quick Google.....
Tire blowouts can be caused by a variety of reasons. A defective rim may cut into the side of the tire or allow the bead to break and the tire to slip from the rim. This kind of damage would usually be obvious so there are few defective rims out there with an owner crazy enough to drive on it. Another cause is too low of air pressure. This causes the tires to flex more than they are designed to during driving. The belts separate and the integrity is comprmized. Air pressure too high can cause a blowout by stressing the tire beyond it's designed limits. One large bump or a hot day can cause that pressure to exceed the bursting limit. Sometimes tires will be manufactured with defects such as air bubbles or poorly mixed rubber. The great Michelin recall comes to mind. Other causes can be vandalism. If vandals slash the sidewall rubber only half way through, this creates a dangerous situation where the cut rubber will tear if you hit a bump, round a turn too fast, or heat up the tire by driving for a long time. Cut rubber can be detected upon close examination. Running over a small sharp object will cause a puncture which leaks air slowly. Running over a large sharp object can tear a large hole, deflating the tire instantly resulting in a blow ou