After a tire explodes, big rigs pull hard to one side and become much harder to steer. For this reason, a truck driver could be jerked into an adjacent lane and even fly into oncoming traffic. A driver who overcorrects increases the odds of rolling over, which can crush vehicles in adjacent lanes.
Many truck drivers overreact to a blowout. For example, they might immediately hit the brakes when it is much safer to maintain regular speeds, at least until they get the truck under control. An unstable vehicle that is suddenly decelerating is an even greater risk.
Blowouts also cause debris to fly around the road. Other motorists might swerve to avoid hitting a big piece of tire and end up pinballing off other vehicles. Tire blowouts can lead to multi-car pileups on the highway, some of which are deadly.