Tanks are relatively heavy. If crawler can reduce the pressure per unit area, the requirements on the road surface can be smaller. Moreover, the defense performance and off-road performance are better than those of wheeled vehicles, and the wheeled structure is simpler than that of tracked vehicles. Generally used in light armored vehicles, the highway speed is better than that of tracked vehicles. Maintenance is also much simpler than tracked vehicles. Tightening the track of that damn tank is a big deal.
Wheeled vehicles are mainly used to drive on flat roads, but there are no flat roads on the battlefield, only various road conditions. In order to face all kinds of road conditions, caterpillar vehicles are used. The advantage of this kind of vehicle is its strong grip, which can reduce the pressure of the tank on the road surface and prevent the tank from falling under the road surface. The heavy suspension system is superior to wheeled vehicles, which can make the tank run more smoothly in various road conditions. Because tires have high requirements for air pressure, sometimes they are easy to burst, which has a great impact on the battle. Tires and tracks are easy to get into muddy roads, but they won't get into them. Because its contact area with the ground is much larger than the contact area between the tire and the ground, it will not fall into the muddy road. So for tanks, crawler vehicles should be used instead of wheeled vehicles.